Under the terms of the 1970 AFL–NFL merger, the NFL began planning to expand from 26 to 28 teams.^[23] In June 1972, Seattle Professional Football Inc., a group of Seattle business and community leaders, announced their intention to acquire an NFL franchise for the city of Seattle.^[24] In June 1974, the NFL gave the city an expansion franchise.^[25] That December, NFL Commissioner Pete Rozelle announced the official signing of the franchise agreement by Lloyd W. Nordstrom, representing the Nordstrom family as majority partners for the consortium.^[26]

In March 1975, the owners hired as general manager John Thompson, a former executive director of the NFL Management Council and former Washington Huskies executive. The name Seattle Seahawks ("seahawk" is another name for osprey) was picked on June 17, 1975, after a public contest that drew more than 20,000 entries proposing more than 1,700 names,^[27] including Skippers, Pioneers, and Lumberjacks.^[28]

Thompson recruited and hired Jack Patera, a Minnesota Vikings assistant coach, to be the first head coach of the Seahawks; the hiring was announced on January 3, 1976. The expansion draft was held March 30–31, 1976, with Seattle and the Tampa Bay Buccaneers alternating picks for rounds selecting unprotected players from the other 26 teams in the league.^[29] The Seahawks were awarded the second overall pick in the 1976 draft, which they used to acquire defensive tackle Steve Niehaus. The team took the field for the first time on August 1, 1976, in a pre-season game against the San Francisco 49ers in the new Kingdome.

The Seahawks are the only NFL team to switch conferences twice since the merger.^[33] The franchise began play in 1976 in the NFC West but switched conferences with the Buccaneers after one season to join the AFC West. This was dictated by the league as part of the 1976 expansion plan, so that both expansion teams could play each other twice and every other NFL franchise once during their first two seasons. The Seahawks won both matchups against the Buccaneers, the first of which was the Seahawks' first regular-season victory.^[34][35]

In 1983, the Seahawks hired Chuck Knox as head coach. Finishing with a 9–7 record, the Seahawks made their first post-season appearance, defeating the Denver Broncos in the Wild Card Round, and then the Miami Dolphins, before losing in the AFC Championship to the eventual Super Bowl champion Los Angeles Raiders. The next season was the Seahawks' best to that point, finishing 12–4; it would remain the franchise's best until 2005.^[36] Knox won the NFL Coach of the Year Award.^[37]

In 1988, Ken Behring and partner Ken Hofmann purchased the team for a reported $80 million.^[38][39][40] The Seahawks won their first division title in 1988, but would miss the playoffs in the next three seasons, after which Knox left the team.^[41] For most of the 1990s, the Seahawks continued to struggle. They saw three consecutive losing seasons (1992–1994) under head coach Tom Flores, including a franchise worst 2–14 season in 1992. After the 1994 season, Flores was fired and Dennis Erickson was brought in as head coach.^{[42][43][44][45][46]}

In 1996, Behring and Hoffman transferred the team's operations to Anaheim, California, although the team continued to play in Seattle. They also contemplated moving the team itself, which was in bankruptcy for a short period. The move was widely criticized. The NFL threatened Behring with a $500,000-per-day fine if he did not move the team's operations back to Seattle.^[47]

The following year, Behring and Hoffman sold the team to Microsoft co-founder Paul Allen for $200 million.^[48]

Erickson's tenure as head coach ended after the 1998 season; the Seahawks missed the playoffs for all four of his seasons with the team, extending their "playoff drought" to ten seasons.^[49]

In 1999, Mike Holmgren was hired as head coach.^[50] He would coach for 10 seasons.^[51] The Seahawks won their second division title, as well as a wild card berth in the playoffs, losing to the Miami Dolphins 20–17.

In 2002, the Seahawks returned to the NFC West as part of an NFL realignment plan that gave each conference four balanced divisions of four teams each. This restored the AFC West to its initial post-merger roster of original AFL teams Denver, San Diego, Kansas City, and Oakland.^[52] That same year, the team opened its new home stadium, Seahawks Stadium, after spending the previous two seasons at Husky Stadium after the Kingdome's implosion in 2000.^[53]

In the 2005 season, the Seahawks had their best season in franchise history (a feat that would later be matched in 2013) with a record of 13–3,^[54] including a 42–0 rout of the Philadelphia Eagles in a Monday Night Football game.^[55] The 13–3 record earned them the top seed in the NFC.^[54] They defeated the Washington Redskins in the Divisional Round and won the NFC Championship Game against the Carolina Panthers, but lost in Super Bowl XL against the Pittsburgh Steelers. The loss was controversial; NFL Films has Super Bowl XL at number 8 on its top ten list of games with controversial referee calls.^[56] Referee Bill Leavy later admitted that he missed calls that altered the game.^[57] Before 2005, the Seahawks had not won a playoff game since the 1984 season, a streak of 21 years (five teams had ever had a drought of twenty years at the time, with their six straight losses being tied for third-most in history). That drought was ended with a 20–10 win over the Washington Redskins in the 2005 playoffs.^[58]

In the 2006 season, the Seahawks finished 9–7 and won the NFC West.^[59] The defeated the Dallas Cowboys 21–20 in the Wild Card Round before losing to the Chicago Bears 27–24 in the Divisional Round.^[60][61] In the 2007 season, the Seahawks finished 10–6 and won the NFC West.^[62] The team defeated Washington in the Wild Card Round 35–14 before losing to the Green Bay Packers in the Divisional Round 42–20.^[63][64] The 2008 season saw the team go 4–12 and finish third in the NFC West.^[65] Holmgren departed from the team after the 2008 season, after the end of his contract.^[66] Defensive backs coach Jim L. Mora was named as Holmgren's successor.^[67] In 2009, the Seahawks finished 3rd in the NFC West with a 5–11 record.^[68] Shortly after, Mora was fired on January 8, 2010 ^[69] and Pete Carroll was hired.

In the 2010 NFL season, the Seahawks made history by making the playoffs despite a 7–9 record.^[70] They had the best record in a division full of teams with losing seasons (Seahawks 7–9, Rams 7–9, 49ers 6–10, Cardinals 5–11) and won the decisive season finale against the Rams (not only by overall record, but by division record, as both teams coming into the game had a 3–2 division record).^[71] In the playoffs, the Seahawks beat the defending Super Bowl XLIV champs, the New Orleans Saints, 41–36. The Seahawks made even more history when Marshawn Lynch made a 67-yard run, breaking nine tackles, to clinch the victory. The fans reacted so loudly that a small earthquake (a bit above 2 on the Richter Scale) was recorded by seismic equipment around Seattle.^[72] Lynch's run would be nicknamed the "Beast Quake". The Seahawks lost to the Bears in their second game, 35–24.^[73] The 2011 season saw the team go 7–9 once again, but they were not able to get into the postseason with a third-place finish in the NFC West.^[74]

The 2012 NFL season started with doubt, as the Seahawks lost their season opener against the Arizona Cardinals. The highly touted Seattle defense gave up a go-ahead score late in the fourth quarter, and rookie quarterback Russell Wilson failed to throw the game-winning touchdown after multiple attempts in the red-zone. However, Russell Wilson and the Seahawks went 4–1 in their next five games en route to an 11–5 overall record (their first winning record since 2007). Their 2012 campaign included big wins over the Green Bay Packers, New England Patriots, and San Francisco 49ers. The Seahawks went into the playoffs as the No. 5 seed and the only team that season to go undefeated at home. In the Wild Card Round, the Seahawks overcame a 14-point deficit to defeat the Washington Redskins.^[75] This was the first time since the 1983 Divisional Round that the Seahawks won a playoff game on the road.^[76] However, in the 2012 Divisional Round, overcoming a 20-point, fourth-quarter deficit would not be enough to defeat the #1 seed Atlanta Falcons. An ill-advised timeout and a defensive breakdown late in the game cost the Seahawks their season, as they lost, 30–28.^[77] Quarterback Russell Wilson won the 2012 Pepsi MAX Rookie of the Year award.^[78]

In the 2013 NFL season, the Seahawks continued their momentum from the previous season, finishing tied with the Denver Broncos for an NFL-best regular season record of 13–3, while earning the NFC's #1 playoff seed.^[79][80] Their 2013 campaign included big wins over the Carolina Panthers, New Orleans Saints, and the San Francisco 49ers.^[81] Six Seahawks players were named to the Pro Bowl: Quarterback Russell Wilson, center Max Unger, running back Marshawn Lynch, cornerback Richard Sherman, free safety Earl Thomas, and strong safety Kam Chancellor.^[82] However, none of them were able to play in the Pro Bowl, as the Seahawks defeated the New Orleans Saints 23–15 and the San Francisco 49ers 23–17, in the playoffs to advance to Super Bowl XLVIII against the Denver Broncos.^[83][84] On February 2, 2014, the Seahawks won the franchise's first Super Bowl Championship, defeating the Broncos 43–8.^[85] The Seahawks' defense performance in 2013 was acclaimed as one of the best in the Super Bowl era.^[86]

The 2014 campaign saw the team lose some key pieces, including wide receiver Golden Tate to free agency and wide receiver Sidney Rice and defensive end Chris Clemons to retirement. Percy Harvin was also let go mid-season after several underachieving weeks and clashes with the rest of the locker room.^[87] Despite starting 3–3, they rallied to a 12–4 record, good enough once again for the #1 seed in the NFC Playoffs.^[88][89] After dispatching the Carolina Panthers handily in the Divisional Round 31–17,^[90] they faced the Green Bay Packers in the NFC Championship Game. Despite five turnovers and trailing 19–7 late in the contest, the Seahawks prevailed in overtime to reach Super Bowl XLIX against the New England Patriots,^[91] but an ill-fated interception at the 1-yard line late in the championship game stymied a comeback attempt and thwarted the Seahawks' bid to be the first repeat Super Bowl champions since the Patriots had won Super Bowls XXXVIII and XXXIX.^[92]

The Seahawks returned to the playoffs in both 2015 and 2016, but despite winning the Wild Card game in both years they failed to win either Divisional round game on the road.^{[93][94][95][96]} The 2017 iteration of the team missed the playoffs for the first time in six years, as injuries to their core players coupled with disappointing acquisitions of running back Eddie Lacy and kicker Blair Walsh failed them in a competitive NFC.^[97] The team cut ties with most of the remaining players that had been part of their meteoric rise and turnover both their Offensive and Defensive coaching staff in 2018, and an influx of young talent helped propel the team to a 10–6 record and another playoff berth that ultimately ended in a loss in the Wild Card game to the Dallas Cowboys.^[98][99] In October 2018, owner Paul Allen died after a prolonged fight with cancer.^[100] In 2019, the Seahawks put up their best record since their last trip to the Super Bowl at 11–5, but they still lost 3 out of their last 4 games and lost their chance to win the NFC West.^[101] A likely explanation for their sloppy finish is because many of their players were injured late in the season. After defeating the Philadelphia Eagles 17–9 in the Wild Card game,^[102] they lost to the Green Bay Packers in the Divisional Round, failing another attempt at a second Super Bowl.^[103]

The 2020 season saw the Seahawks win their first five games, a franchise-best for a start to a season.^[104] Despite the Seahawks losing three of their next four games, the Seahawks finished strong, earning twelve victories for the first time since their Super Bowl season in 2014, and winning the division for the first time in four years.^[105] However, despite the 12–4 record and the division title, the Seahawks' season ended the following week against the Los Angeles Rams, who never trailed in a 30–20 victory.^[106] The Seahawks struggled and started the 2021 season 3–8. Russell Wilson had an injured finger missing 3 games and the Seahawks were shut out the first time in the Wilson era in Week 10 against the Green Bay Packers.^[107] This was their worst first half of a season since 2009, under then-head coach Jim Mora. The Seahawks were eliminated from playoff contention on December 26 in a loss to the Chicago Bears, and they finished last in their division for the first time since 1996.^[108][109] With wins over the Detroit Lions and the Arizona Cardinals they finished 7–10.^[110]

The 2021 season was followed by an offseason of change, punctuated with the trade of quarterback Russell Wilson to the team he and the Seahawks beat in Super Bowl XLVIII, the Denver Broncos, on March 6, 2022. The Broncos traded quarterback Drew Lock, tight end Noah Fant, defensive end Shelby Harris, two first-round picks (for that year's draft, No. 9 overall, and 2023's), two second-round picks (that year's, No. 40 overall, and 2023's) and a 2022 fifth-round selection to the Seahawks for Wilson and a 2022 fourth-round pick. Another hallmark franchise player from the Super Bowl-winning Seahawks, former All-Pro linebacker Bobby Wagner, was cut by the team that same day, a move that saves them $16.6 million in cap space. The Seahawks also took on $26 million in dead money by trading Wilson; ESPN Stats & Information research revealed it to be the second-most dead money a team has ever incurred, trailing the $33.8 million the Philadelphia Eagles ate in their trade of Carson Wentz the previous year.^[111]

In the 2022 season, the Seahawks finished with a 9–8 record and made the playoffs.^[112] The team's season ended in the Wild Card round with a 41–23 loss to the San Francisco 49ers.^[113] The 2023 season saw the Seahawks finish 9–8 and miss the postseason.^[114] Carroll was fired from his head coaching position after the 2023 season.^[115] Carroll remained with the team in an unspecified advisory role.^[116]

Mike Macdonald, formerly defensive coordinator of the Baltimore Ravens, was hired as the new head coach.^[117] In the 2024 season, the Seahawks went 10–7 but missed the postseason.^[118]

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When the Seahawks debuted in 1976, the team's logo was a stylized royal blue and forest green osprey's head based on Kwakwakaʼwakw art masks.^[119] The helmet and pants were silver while the home jerseys were royal blue with white and green sleeve stripes and white numerals and names. The road jersey was white, with white, blue and green sleeve stripes and had blue numerals and names. The socks were blue and had the same green and white striping pattern seen on the blue jerseys. Black shoes were worn for the first four seasons, one of the few NFL teams that did so in the late 1970s, at a time when most teams were wearing white shoes. They would switch to white shoes in 1980.^[120][121]

In 1983, coinciding with the arrival of Chuck Knox as head coach, the uniforms were updated slightly. The striping on the arms now incorporated the Seahawks logo, and the TV numbers, previously located on the sleeves, moved onto the shoulders. The helmet facemasks changed from gray to blue. Also, the socks went solid blue at the top, and white on bottom.^[122] In the 1985 season, the team wore 10th Anniversary patches on the left side of their pants. It had the Seahawks logo streaking through the number 10. In 1994, the year of the NFL's 75th Anniversary, the Seahawks changed the style of their numbering to something more suitable for the team; Pro Block from then until 2001. That same year, the Seahawks wore a vintage jersey for select games resembling the 1976–82 uniforms. However, the helmet facemasks remained blue. The logos also became sewn on instead of being screen-printed. In 2000, Shaun Alexander's rookie year and Cortez Kennedy's last, the Seattle Seahawks celebrated their 25th Anniversary; the logo was worn on the upper left chest of the jersey. In 2001, the Seahawks switched to the new Reebok uniform system still in their then-current uniforms after that company signed a 10-year deal to be the exclusive uniform supplier to the NFL, but it would be their last in this uniform after the season ended. Before this, various companies made the team's uniforms.

On March 1, 2002, to coincide with the team moving to the NFC as well as the opening of Seahawks Stadium, both the logo and the uniforms were heavily redesigned. The Wordmark was designed by Mark Verlander and the logo was designed by NFL Properties in-house design team. The colors were modified to a lighter "Seahawks Blue", a darker "Seahawks Navy" and lime green piping. The helmets also were changed from silver to the lighter "Seahawks Blue" color after a fan poll was conducted. Silver would not be seen again until 2012. The logo artwork was also subtly altered, with an arched eyebrow and a forward-facing pupil suggesting a more aggressive-looking bird. At first, the team had planned to wear silver helmets at home and blue helmets on the road, but since NFL rules forbid the use of multiple helmets, the team held the fan poll to decide which color helmet would be worn. The team had usually worn all blue at home and all white on the road since 2003, but late in the 2009 season, the Seahawks wore the white jersey-blue pants combo. The blue jersey and white pants combo has been worn for only one regular-season game, the 2005 season opener at the Jacksonville Jaguars, while the white jersey and blue pants combination has not been worn regularly since late in the 2002 season, with the exception of late in the 2009 season. In 2009, the Seahawks once again wore the white jersey and blue pants combination for road games against Minnesota (November 22), St. Louis (November 29), Houston (December 13), and Green Bay (December 27).

The Seahawks wore their home blue jerseys during Super Bowl XL despite being designated as the visitor, since the Pittsburgh Steelers, the designated home team, elected to wear their white jerseys.

On September 27, 2009, the Seahawks wore lime green jerseys for the first time, paired with new dark navy blue pants in a game against the Chicago Bears. The jerseys matched their new sister team, the expansion Seattle Sounders FC of Major League Soccer who wear green jerseys with blue pants. On December 6, 2009, the Seahawks wore their Seahawks blue jersey with the new dark navy blue pants for the first time, in a game against the San Francisco 49ers. The Seahawks broke out the same combo two weeks later against the Tampa Bay Buccaneers, and two weeks after that in the 2009 regular-season finale against the Tennessee Titans. In December 2009, then-coach Jim Mora announced that the new lime green jerseys were being retired because the team did not win in them, because he liked the standard blue home jerseys better, and added that the home jersey is a better match for the navy pants.^[123] In the same press conference, he stated that the new navy pants "felt better" on players as opposed to the Seahawks blue pants. For the 2010 season, Seattle returned to the traditional all "Seahawks Blue" at home and all white on the road.

On April 3, 2012, Nike, which took over as the official uniform supplier for the league from Reebok, unveiled new uniform and logo designs for the Seahawks for the 2012 season. The new designs incorporate a new accent color, "Wolf Grey", and the main colors are "College Navy" and "Action Green".^[5][6] The uniforms incorporate "feather trims", multiple feathers on the crown of the helmet, twelve feathers printed on the neckline and down each pant leg to represent the "12th Man", referring to the team's fans.^[124][125] The Seahawks have three different jersey colors: navy blue, white, and an alternate grey jersey. The Seahawks will have three different pants: navy blue with green feathers, gray with navy blue feathers, and white with navy blue feathers. Their new logo replaces the Seahawk blue with wolf grey. Altogether, there are nine different uniform combinations possible.

The Seahawks wore their Nike home blue jerseys for the first regular-season game on September 16, 2012, against the Dallas Cowboys. The uniform Marshawn Lynch wore in that game is preserved at the Pro Football Hall of Fame.^[126] On September 9, 2012, the Seahawks wore their Nike white away jerseys for the first regular-season game against the Arizona Cardinals; on October 14, 2012, with the Carolina Panthers wearing white at home, they wore their blue jerseys with gray pants (and would do so again against the Miami Dolphins seven weeks later); and on December 16, 2012, they wore their Alternate Wolf Grey jerseys for the first time against the Buffalo Bills.^[127]

The all-navy ensemble is the Seahawks' current primary uniform option for home games. Initially, the Seahawks paired their navy uniforms with gray pants on select road games in which the home team wore white jerseys, but on December 5, 2021, the Seahawks wore this combination at home for the first time in a game against the San Francisco 49ers. On the road, the Seahawks primarily pair their white uniforms with the navy pants (that combination was used during their Super Bowl XLVIII win), although they also pair the white uniforms with either white or gray pants on occasion. The all-gray uniforms were worn occasionally on the road, mainly against the Arizona Cardinals.

In 2016, the Seahawks unveiled their NFL Color Rush uniform, an all-Action Green ensemble.^[128] They first wore the uniform on December 16 against the Los Angeles Rams at home, marking the first time they wore green uniforms since 2009. The Seahawks continue to wear the Color Rush set as an alternate uniform alongside the all-gray combination.

During a home matchup with the Vikings on December 3, 2019, the Seahawks wore their Color Rush green tops and regular navy pants.^[129] The combination was used again on October 11, 2020, also against the Vikings, and then again on November 19, against the Arizona Cardinals. It was used once in 2021, on Thursday Night Football vs. the Rams.

In July 2023, the Seahawks introduced a throwback uniform set inspired by the team's 1983–2001 design. These uniforms were worn in Week 8 against the Cleveland Browns.^[130] Consequently, the gray alternate tops were retired due to NFL regulations restricting teams to two alternate jerseys.^[131]

The Seahawks were long the only NFL team to have never worn white jerseys in a home game.^[132] That changed on September 24, 2023, when the team wore white jerseys at home against the Carolina Panthers. The game marked the 10th anniversary of the Seahawks' first Super Bowl victory, as the current team wore the same white jersey/navy pants combination from Super Bowl XLVIII.^[133]

During the 2025 NFL Draft, the NFL and Nike announced that the NFC WEST and AFC EAST would debut a "rivalry uniform" in the 2025 season that will be worn once a season against a division rival. The new fifth uniforms were intended to connect to the teams' cities, like the MLB’s City Connect uniforms.^[134] On August 28, 2025, the new "High-Decibel Zone" Rivalries uniform was unveiled. In Wolf Grey and Iridescent Green, the design marks a return of the uniform color the team gave up in favor of the throwbacks the prior season. The green, a first of its kind in the NFL, features a metallic sheen that seems to change color depending on lighting and viewing angle.^[135]

The jersey features a unique iridescent green soundwave design on the upper chest and shoulders, as well as down the sides of the pants, meant to represent the notorious loudness of the fanbase at Lumen Field. Bordered in navy blue, the player numbers on the front and back are in the same green material with small repeating "12"s replacing the "feather" pattern of the standard uniform numbers. A green "12" patch is placed at the back of the collar. Navy blue stripes appear around the collar, at the bottoms of the sleeve cuffs, and down the sides of the pants. With wolf grey gloves, any additional items like tees, sleeves, and leg tights are in navy blue. The striking iridescent green helmet has a metallic chrome finish, making the color appear to alternate between green and blue in the light. The logo appears in white outline and the phrase "12 AS ONE" sits at the bottom of the back of the helmet.^[135]

The rivalry between the Seahawks and Los Angeles Rams came into existence in 2002 after the Seahawks moved to the NFC West. The first notable matchup between the two clubs occurred in the 2004 NFC Wild card round when the Rams managed to defeat the Seahawks in Seattle 27–20 and currently hold the streak for the only two wins against the Seahawks at home during the postseason. Much of the intensity waned as the Rams declined in competition throughout the 2000s and early 2010s, but several notable matchups between the two clubs would still occur. The rivalry saw new life as the Rams' Mob Squad-era teams regularly clashed with Seattle's Legion of Boom era teams, often escalating into bitter grudge matches for control of the division.^[136][137] After the Rams' return to Los Angeles in 2016, and subsequent playoff success (most recently with a Super Bowl victory in 2022); the rivalry has increased in intensity; especially as Seattle's Legion of Boom era teams waned in competition.^[138] Due to the recent dominance by the Rams under Sean McVay and former defensive tackle Aaron Donald, Seahawks fans have recently viewed the Rams as their divisional arch rival.^[139] Tensions especially ran high during the 2021 Wild Card game after a widely publicized taunt from Safety Jamal Adams during a postgame conference after a tough win over the Rams during week 16. The Rams would go onto decimate the Seahawks in the wild card game, with cornerback Jalen Ramsey and quarterback Jared Goff expressing their satisfaction to get retribution after Adams' comments and cigar gesture.^[140]

As of the 2024 season, the Seahawks lead the series 28–27, but the Rams have won both playoff meetings.^[141]

From 2011 to 2014, the Seahawks and the San Francisco 49ers emerged as two of the best teams in the NFC, and developed a rivalry as a result. The 49ers head coach at the time, Jim Harbaugh, had a contentious history with Seahawks coach Pete Carroll due to Harbaugh's previous job as coach at Stanford against Carroll's USC Trojans. Harbaugh's 49ers won the first three head-to-head contests but lost Week 16 of 2012. Both teams reached the playoffs that year, however the 49ers reached Super Bowl XLVII, which they lost. In 2013, the Seahawks won in a Week 2 contest, but the 49ers would triumph in Week 14. The Seahawks would beat the 49ers in the 2013 season NFC Championship Game 23–17 in a controversial win. The Seahawks went on to win the next 10 matchups, sweeping the regular season series against the 49ers from 2014 to 2018. After splitting games in 2018 and 2019, the 49ers won 6 straight against the Seahawks, including the 2022 wild card game. The Seahawks won the second matchup of 2024 to end the streak.

As of the end of the 2024 season, the Seahawks lead the series 31–23.^[142]

The Arizona Cardinals and Seahawks became divisional rivals after both were moved to the NFC West during the league's 2002 realignment. This rivalry has become one of the NFL's more bitter in recent years, as the mid-to-late 2010s often saw the Seahawks and Cardinals square off for NFC West supremacy. The rivalry hit its peak as the Cardinals frequently clashed with the Legion Of Boom-era Seahawks led by Russell Wilson and head coach Pete Carroll, although Seattle shares more intense rivalries with the Rams and 49ers. Despite this, the two teams have been known to beat each other on their respective home fields, with Seattle having more wins against the Cardinals in Arizona than Seattle, and vice versa. Seattle leads the series 30–22–1, and the two teams have yet to meet in the playoffs.^[143]

Since moving to the NFC, the Seahawks have faced the Green Bay Packers several times in the playoffs, developing an intense rivalry as well. Some notable moments include the clubs' first playoff meeting in 2003 in which Seahawks quarterback Matt Hasselbeck threw a game-losing pick-six in overtime after guaranteeing a game-winning drive,^[144] the Fail Mary, and Russell Wilson overcoming four interceptions and a 16–0 Packers lead to lead Seattle to a 28–22 overtime win to advance to Super Bowl XLIX.^[145] As of the 2024 season, the Packers lead the all-time series 16–9.^[146]

From the 1980s to the 2002 league realignment, the Denver Broncos were a major rival for the Seahawks.^[147][148] As of the 2023 season, the Broncos lead 35–23 against the Seahawks with Seattle having won both postseason meetings.^[149] Since 2002, Denver has won three of five interconference meetings, and the teams met in Super Bowl XLVIII on February 2, 2014, where the Seahawks won 43–8.^[150] On March 8, 2022, the Seattle Seahawks agreed to trade Russell Wilson and a 2022 fourth-round pick to the Denver Broncos for quarterback Drew Lock, tight end Noah Fant, defensive lineman Shelby Harris, two first-round picks (2022—No. 9 overall—and 2023), two second-round picks (2022—No. 40 overall—and 2023) and a 2022 fifth-round selection.^[151] Russell Wilson's first game against the Seattle Seahawks as a member of the Denver Broncos was played September 12, 2022, on Monday Night Football, where the Seahawks won 17–16.^[152]

The Raiders and Seahawks played many times being old members of the AFC West. Seattle's move to the NFC has made the matchup occur much less frequently, playing only five times since the end of the 2002 season. The Raiders lead the all-time series 30–26.^[153]

During the Seahawks' first ten seasons (1976–85), the team's headquarters was in Kirkland at the southern end of the Lake Washington Shipyard (now Carillon Point), on the shores of Lake Washington.^[154] The summer training camps were held across the state at Eastern Washington University in Cheney, southwest of Spokane.

When the team's new headquarters across town in Kirkland was completed in 1986, the Seahawks held training camp at home for the next eleven seasons (1986–96), staying in the dormitories of the adjacent Northwest College. In 1997, Dennis Erickson's third season as head coach, the team returned to the hotter and more isolated Cheney for training camp, which continued through 2006. In 2007, training camp returned to the Seahawk's Kirkland facility because of the scheduled China Bowl (NFL) game, which was later canceled. In 2008, the Seahawks held the first three weeks of camp in Kirkland, then moved to the new 19-acre (77,000 m²) Virginia Mason Athletic Center (VMAC) on August 18 for the final week of training camp, where the team has held their training camps since. The new facility, adjacent to Lake Washington in Renton, has four full-size practice fields: three natural grass outdoors and one FieldTurf indoors.^[155]

The Seattle Seahawks have competed in 50 NFL seasons, dating back to their expansion year of 1976. The team has compiled a 402–373–1 (.519) regular-season record and a 17–19 (.472) record in the playoffs, for an overall record of 419–392–1 and a .517 winning percentage.^[156] Seattle has reached the playoffs in 20 separate seasons, including in the 2005 season when they lost Super Bowl XL to the Pittsburgh Steelers, the 2013 season when they defeated the Denver Broncos to win Super Bowl XLVIII, and the 2014 season when they lost Super Bowl XLIX to the New England Patriots. In the 2010 season, the Seahawks became the first team in NFL history to earn a spot in the playoffs with a losing record (7–9, .438) in a full season; this was by winning the division. The Seahawks would go on to defeat the reigning Super Bowl champion New Orleans Saints in the Wild Card round, becoming the first team ever to win a playoff game with a losing record. Until Week 7 of the 2016 season against the Arizona Cardinals, the Seahawks had never recorded a tied game in their history.^[157]

The 35th Anniversary team was voted upon by users on Seahawks.com and announced in 2010.^[158] Bold indicates those elected to the Pro Football Hall of Fame.

The Seahawks have retired five numbers in franchise history.^[159]

• † Jerry Rice wore No. 80 for his 2004 stint with the Seahawks. According to Rice, the team offered him the jersey number, with Largent's permission.^[166]
• Several other players and individuals related to the team have been honored by their induction into the Seattle Seahawks Ring of Honor

Note: Although Mike McCormack served as head coach, president, and general manager for the Seahawks, he is only listed in the Pro Football Hall of Fame for his contributions as a tackle for the New York Yanks and the Cleveland Browns.

• Nordstrom estate & Herman Sarkowsky: 1976–1988
• Ken Behring & Ken Hofmann: 1988–1996
• Paul Allen: 1997–2018
• Allen estate, managed by Jody Allen: 2018–present^[167][7]

The Seahawks have had nine head coaches in franchise history.^[168]

The 12s (formerly the 12th man) refers to the fan support of the Seahawks.^[169] The team's first home stadium, the Kingdome, was one of the loudest and most disruptive environments in the NFL.^[170] Opponents were known to practice with rock music blaring at full blast to prepare for the often painfully high-decibel levels generated at games in the Kingdome.

In 2002, the Seahawks began playing at what is now Lumen Field. Every regular-season and playoff game at Lumen Field since the second week of the 2003 season has been played before a sellout crowd. Like the Kingdome before it, Lumen Field is one of the loudest stadiums in the league. The stadium's partial roof and seating decks trap and amplify the noise and reflect it back down to the field. This noise has caused problems for opposing teams. From 2002 through 2012, there were 143 false-start penalties on visiting teams in Seattle, second only to the Minnesota Vikings.^[171]

The Seahawks' fans have twice set the Guinness World Record for the loudest crowd noise at a sporting event, first on September 15, 2013, registering 136.6 dB during a game against the San Francisco 49ers^[19] and again on December 2, 2013, during a Monday Night Football game against the New Orleans Saints, with a roar of 137.6 dB.^[20][21] As of September 29, 2014, the record of 142.2 dB is held in Arrowhead Stadium by fans of the Kansas City Chiefs.^[172]

Before kickoff of each home game, the Seahawks salute their fans by raising a giant #12 flag at the south end of the stadium.^[173] Current and former players, coaches, local celebrities, prominent fans including Patti Hammond, Seattle-area athletes, and former owner Paul Allen have raised the flag. Earlier, the Seahawks retired the #12 jersey on December 15, 1984, as a tribute to their fans.^[160] Before their Super Bowl win, the Seahawks ran onto the field under a giant 12th Man flag.

In September 1990, Texas A&M University filed, and was later granted, a trademark application for the "12th Man" term, based on their continual usage of the term since the 1920s. In January 2006, Texas A&M filed suit against the Seattle Seahawks to protect the trademark and in May 2006, the dispute was settled out of court. In the agreement, which expired in 2016, Texas A&M licensed the Seahawks to continue using the phrase, in exchange for a licensing fee, public acknowledgement of A&M's trademark when using the term, a restriction in usage of the term to seven states in the Northwest United States, and a prohibition from selling any "12th Man" merchandise.^{[174][175][176]} Once the agreement expired, the Seahawks were allowed to continue using the number "12" but were no longer permitted to use the "12th Man" phrase.^[177] In August 2015, the Seahawks decided to drop their signage of the "12th Man" term and shifted towards referring to their fans as the "12s" instead.^[178]

Starting in the 1998 season, Blitz has been the Seahawks' official mascot.^[179] Before the 2014 NFL season, Blitz was given a new look and a sidekick; a secondary mascot named Boom was introduced to appeal to and interact with younger children.^[180][181]

In the 2003 and 2004 seasons, a hawk named Faith would fly around the stadium just before the team came out of the tunnel. However, because of her relatively small size and an inability to be trained to lead the team out of the tunnel, Faith was replaced by an augur hawk named Taima before the start of the 2005 NFL season. Taima started leading the team out of the tunnel in September 2006.^[182][183]

A group of female and male cheerleaders known as the Seahawks Dancers rallies the crowd from the sidelines and performs a halftime routine during home games at Lumen Field. The group was an all-female squad called the Sea Gals until it admitted male members and was renamed before the 2019 NFL season.^[184][185] During the off-season, a unit of the Dancers travels to parades and other events, as well as with other NFL cheerleaders on the road.

Beginning in 2004, the Seahawks introduced their drum line, the Blue Thunder.^[186] The group plays at every home game and at other Seattle events.

The Seahawks' flagship station is KIRO 710 kHz – KIRO-FM 97.3 MHz.^[188] Games are heard on 47 stations in five western states and Canada.^[189] Microsoft holds naming rights for the broadcasts for their web search engine under the moniker of the "Bing Radio Network". The current announcers are former Seahawks players Steve Raible (who was the team's color commentator from 1982 to 2003) and Dave Wyman.^[190] The Raible-Wyman regular season pairing has been together since the final four games of 2017 but became full time starting in 2018. On local television broadcast preseason games are split between former Seahawks Paul Moyer, Sam Adkins, and Brock Huard. Pete Gross, who called the games from 1976 until just days before his death from cancer in 1992, is a member of the team's Ring of Honor. Other past announcers include Steve Thomas from 1992 to 1997, Lee Hamilton (also known as "Hacksaw") from 1998 to 1999, Brian Davis from 2000 to 2003, and former Seahawk Warren Moon from 2004 to 2017.

Preseason games not shown on national networks were produced in-house by Seahawks Broadcasting and televised by KING-TV, channel 5 (and, in 2008, also on sister station KONG-TV since KING, an NBC affiliate, was committed to the Summer Olympics in China). Kate Scott became the announcer for Seahawks TV preseason games in 2023, replacing Curt Menefee (the host of Fox NFL Sunday) who had been the Seahawks TV voice since the 2009 preseason. KCPQ-TV, which airs most of the Seahawks' regular-season games (as the Seattle-Tacoma area's Fox affiliate), became the television partner for the team in 2012 and replaced KING-TV as broadcaster for preseason games, but KING-TV regained the partnership in 2022; simulcasts of any Seahawks games on ESPN's Monday Night Football air (as of the 2018 season) on CBS affiliate KIRO-TV.^[191][192] In addition, any Saturday or Sunday afternoon games broadcast by CBS (usually—but not always—with the Seahawks hosting an AFC opponent) will air on KIRO-TV.