The 2006 English cricket season was the 107th in which the County Championship had been an official competition. It included home international series for England against Sri Lanka and Pakistan. England came off a winter with more Test losses than wins, for the first time since 2002-03, but still attained their best series result in India since 1985. The One Day International series against Pakistan and India both ended in losses.

In domestic cricket, Nottinghamshire, holders of the County Championship, were relegated, and it was Sussex who took the Championship title as their Pakistani overseas player Mushtaq Ahmed ended with 102 wickets. Sussex pipped Lancashire to the title, as they did in the one-day C&G Trophy, which was changed from a direct knock-out into two regional leagues of 10, from which two teams progressed to the final at Lord's, where Sussex won by 15 runs. Essex Eagles defended their National League title from last season, a league tournament that has been shortened from 16 to eight matches per side and officially named Pro40. They finished level with Northamptonshire Steelbacks in the table, though the Steelbacks lost by 109 runs in their meeting. The Twenty20 Cup completed its fourth instalment during 2006, and was won by Leicestershire Foxes, the first team to win the Twenty20 Cup twice.

The season's opening first class game, the Champion County match at Lord's, began on 14 April with a Marylebone Cricket Club team taking on Nottinghamshire. Nottinghamshire earned a lead of 23 on first innings after bowling MCC out for 168, and after centuries from Jason Gallian, Chris Read and Mark Ealham, they declared with a day to spare. Despite 94 from No. 8 Tim Bresnan, MCC lost by 142 runs. A day later, the six three-day university matches between county teams and university teams had begun: the matches were all drawn, though no county team failed to bowl out their opponents in the first innings, and all county teams declared their first innings closed.

On 18 April, the County Championship began, but the first matches were dominated by rain; at Old Trafford, Lancashire and Hampshire played out 169.3 overs, compared to the minimum of 408 set out in ECB regulations, in a drawn game, while Gloucestershire overcame Somerset in Division Two despite 36 and 172 from Australian overseas player Cameron White. Excluding extras, the other ten players contributed with 197 runs, eleven less than White. The other five matches began a day later: Durham's first outing in Division One ended with victory, as Gordon Muchall hit 219 in the first innings and Kent were bowled out for 340 and 179 to leave Durham with a win by an innings and 56 runs, while Nottinghamshire, Yorkshire, Sussex and Warwickshire all recorded draws. In Division Two, Surrey's first match after relegation saw them save the draw after following on against last year's wooden spoon winners Derbyshire, and Essex and Northamptonshire also drew. Two of the three university matches that week had two days rained out; the third, between Middlesex and Oxford UCCE was drawn.

The first round of the league stage of the C&G Trophy was played out on 23 April. In the South Conference, Essex (in a 10-over affair), Gloucestershire, Hampshire and Somerset (after Marcus Trescothick's 158) recorded wins, while Derbyshire, Lancashire and Worcestershire won in the North. Sri Lanka began their tour the following day, drawing with a British Universities XI at Fenner's, and the second round of the Championship took place from 26 April to 29 April with seven matches. Durham fell back to earth after their initial win, giving up 421 runs in the first innings to Lancashire and losing by 128 runs, while Pakistanis Naved-ul-Hasan and Mushtaq Ahmed claimed 14 of 20 wickets for Sussex in their win at Hampshire, who failed to pick up batting points for the second time this season. Kent chased down 354 for the loss of three wickets against Middlesex at Lord's, and Warwickshire, despite giving up 433 in the fourth innings, beat Yorkshire to go top of the table.

In Division Two, Essex made 639 with three centuries before declaring against Glamorgan, which was enough to win by an innings and 30. Essex thus topped the table, while Glamorgan was bottom. Surrey beat Leicestershire by 99 runs, and Somerset beat Worcestershire in a match where three of the innings totalled less than 170 runs, and Somerset's first was worth 406 and full batting points. Meanwhile, three counties played university matches, with Nottinghamshire and Gloucestershire recording innings victories while Northamptonshire came back from a four-run first innings deficit against Cambridge to win by 193 runs.

The last matches of the month were those of the second round of the C&G Trophy, along with Derbyshire's tour match against Sri Lanka. Derbyshire got a first innings lead of 43 after Sri Lanka declared their first innings closed, and Australian Travis Birt hit 83 off 53 balls before Derbyshire declared overnight on 208 for 4. In the C&G Trophy, Ireland bounced back from an early loss when they successfully defended 193 against Gloucestershire, while Warwickshire made 352 for two against Scotland to win by 114 runs, and Sussex converted seven for two into a successful chase of 273 against Surrey.

On 1 May, nine matches were played in the C&G Trophy, with only Derbyshire and Yorkshire resting. Five of the matches were affected by rain, though no team played fewer than 30 overs. In the North, Durham won their first one-day game of the season, Scotland suffered their second loss in as many days at the hands of Nottinghamshire, Lancashire were the only team with two wins after bowling Worcestershire out for 129, while Warwickshire's 128 for 9 in 33 overs led to loss against Leicestershire.