SmartLink is a RFID-enabled credit card-sized smartcard that is the primary fare payment method on the PATH transit system in Newark and Hudson County in New Jersey and Manhattan in New York City. It was designed to replace PATH's paper-based farecard, QuickCard, and there was plans to expand its usage throughout most transit agencies in the tri-state area. The SmartLink card has been available to the public since July 2, 2007. Although the MetroCard used on the Metropolitan Transportation Authority (MTA)'s transit system can also be used on the PATH, the reverse is not true for SmartLink, which cannot be used on the MTA's system.

All SmartLink cards are eligible for online registration. In order to register a card, one must simply go to PATH's registration page and complete a form detailing the card holder's name, the unique serial code of the SmartLink card, and address. An account holder's information can be accessed online or by calling the SmartLink hotline. Money from lost cards can be transferred to a replacement card if the customer has an account; however, all replacement cards carry a $5 fee.

Registration of the card also permits the holder to monitor its usage and to link the SmartLink card to a credit card in the automatic replenishment program. When the card balance drops to five trips (or five days, for riders with an unlimited pass), the SmartLink card is topped up using the credit card on the account. This program can be managed online, on the PATH website.

Pre-loaded SmartLink cards with 10 trips are available at all stations for $31.00 (10 trips at $2.60 each, plus a $5.00 card fee). However, MetroCard Vending Machines (MVMs) at all PATH stations are able to refill the SmartLink cards to a monetary amount equal to 1, 2, 4, 10, 20 and 40 trips as well as the daily or 30 day unlimited passes.

$5.00 SmartLink Cards with no trips, ready for charging at any PATH MetroCard Vending Machine, are available from vending machines at 33rd Street, Hoboken, Journal Square, Exchange Place, Newport and World Trade Center.

SmartLink card can be purchased via the SmartLinkSM Card Dispensers (33rd Street, Hoboken, Journal Square, Newark, World Trade Center). Zero trip and 20 trip cards ($57.00 (20 trips at $2.60 each, plus a $5.00 card fee) are also available for purchase online on the PATH website. At one time Pre-loaded SmartLink Cards were available at newsstands in PATH terminals but PATH has discontinued this.

When buying a SmartLink card for the first time, an additional, one-time $5 fee is levied to offset the cost of producing the card. The cards can be refilled in specified numbers of trips or by adding unlimited passes. When refilling, the regular fare structure is used and the $5 card purchase fee is not imposed. As of November 1, 2019 the following fare structure is in effect:

The maximum number of trips that can be loaded on the card is 140. An unlimited pass can be loaded on top of a regular trip SmartLink card. When that occurs, the individual rides will remain in the background of the card. When the unlimited pass expires the individual trips will be available for use.