Free Agency
Six years of major league service and a player can sign with anybody, which is the whole shape of how baseball pays people.
What it actually is. A player becomes a free agent after six years of major league service time and can then sign with any club. Before that he belongs to the club that has him, at a salary the club largely controls. A club losing a free agent may attach a qualifying offer, which brings draft pick compensation if he signs elsewhere.
What somebody who knows the game gets out of it. The six year rule creates the central economic fact of the sport: players are underpaid for their best years and paid for them afterwards. A player debuting at 23 reaches free agency at 29, having given the club his peak at a fraction of market value, and then signs a long contract covering his decline. Everything about how clubs behave, service time manipulation, extensions for young players, reluctance to sign anybody past 32, follows from that single structure.
The numbers worth knowing. Six years of service, 172 days making a year. A win on the free agent market has cost roughly eight to nine million dollars in recent years. A player's peak is typically 26 to 29, which is almost exactly the window before free agency.
What people get wrong about it. Service time is counted in days, not seasons, which is why a club calling a player up in late April rather than on Opening Day can gain a whole extra year of control. The rules were changed to add draft pick incentives against this, and it still happens.
At Little League and travel ball. No equivalent, but understanding it explains most of the news a young fan hears in the winter. It is also worth knowing for the college and draft path this site covers, because the same clock starts the day a drafted player reaches the majors, not the day he signs.
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