A Free Agent is, quite simply, someone who is not currently under contract. You are (most likely) an NFL free agent. More interestingly, there are a lot of players in the NFL who are in a nebulous grey area between under contract and a free agent. How can this be? The NFL has a labor contract with the NFL Players Association, called the Collective Bargaining Agreement, the CBA. The CBA defines several types of Free Agent depending on previous experience and club offers. Previous experience means "accrued seasons." An accrued season means six or more regular-season games on a club's active/inactive, reserved- injured or "physically unable to perform" lists.
In the NFL there are five classes of free agent. Most of the classes have sub-classes. It's all quite complicated.
Unrestricted Free Agents (UFA)
An Unrestricted Free Agent is a player who is not under contract with any team. This player may sign a contract with any NFL team, and their previous team gets no compensation in any form. You become a UFA if you get cut, or if your contract runs out and you have at least four years of NFL experience. The signing period for unrestricted free agents begins March 2 and concludes on July 22 (or the first scheduled day of the first NFL training camp, whichever is later).
UFAs are free to sign with any club through July 22 or the first scheduled day of the first NFL training camp, whichever is later. On July 23, their exclusive rights will revert to their original club if that club made a June 1 tender at the veteran minimum to the player. Teams will have until the 10th week of the season (Nov. 15) to sign their unrestricted veteran free agents. If the player does not sign by Nov. 15, he must continue to sit out the remainder of the season. If a June 1 tender is not made to an unrestricted free agent, he continues to be free to sign with any club.
Restricted Free Agents (RFA)
A Restricted Free Agent is an NFL player who is not under contract, but has only three years of NFL experience. The signing period for restricted free agents begins on March 2 and concludes on April 15. If his previous team has made him a Qualifying Offer, then that team has a right of first refusal on the player. This means the player may negotiate with other teams and receive an offer, however the previous team may agree to the offer that the player has received, in which case the player stays with his former team. Of course there are lots of games played, the prospective new team will attempt to structure the offer so that it is very unpalatable to the new team. For example, a team with a lot of cap room can offer a large salary and small signing bonus which is difficult for another team to match. Or a team with a very bad record can offer a large bonus based on winning 10 games, which would be unlikely to be earned on the new team but perhaps likely to be earned on the original team, thus making the offer have a large cap number.
There are three levels of Qualifying Offer. Each level has an associated salary which is part of the CBA. In 2005 the three qualifying offer levels are $656,000, $1.43M, and $1.9M.
If the team offers the player the lowest qualifying salary, then that's the player's salary if he gets no offers in free agency. If he gets an offer, his current team has a choice: they can match the offer exactly, or they can let the player go, in which case they will get a draft pick from the new team which is the same as the draft pick they used to get the player. If the player was selected in the 6th round, then the old team gets the new team's 6th round draft pick in the next year. If the player was undrafted, the old team gets no draft pick.
If the team offers the player the middle level salary, then that's the player's salary if he gets no offers. If he gets an offer, then the old team can match the offer. If they do not, then the old team gets a 1st round draft pick from the new team.
If the team offers the player the top level qualifying offer, then that's the player's salary if he gets no offers. If the old team does not match an offer, then they get a 1st round and a 3rd round draft pick from the new team.
Exclusive-Rights Free Agents (ERFA)
An Exclusive-Rights Free Agent is an NFL player who is not under contract, but has only two years of NFL experience. If his former club makes him an offer at the three year veteran minimum salary, then that's it, he has to take it or leave the NFL. These guys have no right to negotiate with other teams. They are "free" only in the sense that they're free to quit.
Transition and Franchise Tags
Each team has one "tag" they can use to lock up a player. They may choose for their tag to be the transition tag, the franchise tag, or the exclusive rights franchise tag. If their one tag is not being used on another player, then the team may choose to designate one of their players as their Transition Free Agent. This name is left over from 1993, when free agency was started and teams were very afraid of losing their top players.
Most times, the transition and franchise tag is used by a team to buy time while a long-team contract is being negotiated. If the player is designated a transition or franchise player and signed immediately to a long term contract, then he retains the tag for the duration of the contract and the team may not use the transition or franchise tag on another player until the contract is done. So what teams invariably do is negotiate a long term contract. When the new contract is agreed, then the player signs his transition or franchise contract, locking up the tag for a year. Then the player signs the long team contract the next day, which voids the one year contract and frees up the transition / franchise tag for use on another player. In the event a player retires, suffers a career-ending injury or is otherwise unavailable due to non-football circumstances, a club has the right to designate another franchise or transition player for the remaining years covered by the club's prior designation.
A club may withdraw a franchise or transition designation at any time. The player becomes an unrestricted free agent when that withdrawal occurs, and the team can use one of the designations on another player at the appropriate time.
Transitional Free Agents (TFA)
A transition player designation gives the club a first refusal right to match an offer sheet given to the player by another club. To designate a transition player, the club must offer a minimum of the average of the top 10 salaries of the previous year at the player's position, or a 20 percent salary increase, whichever is greater. If the player does not get an offer, then he must play for the transition offer. If the player gets an offer, then his previous team has seven days to match the offer or lose the player. If they do not match the offer, the previous team gets no compensation.
Franchise Free Agents (FFA)
A franchise player is offered a minimum of the average of the top five salaries at his position in the previous season, or a 20 percent salary increase, whichever is greater. This type of franchise player may negotiate with other clubs. His original club has seven days to match the offer and retain the player, or receive two first-round draft choices as compensation if the original club elects not to match.
Exclusive Franchise Free Agents (EFFA)
The second type of franchise player is offered a minimum of the average of the top five salaries at his position computed on April 15th at the end of restricted free agency, or a 20 percent salary increase, whichever is greater. This type of franchise player may negotiate with other clubs. Other clubs cannot negotiate with exclusive franchise players.