Owners overwhelmingly approved a proposal last week, but some unresolved issues still needed to be reviewed to satisfy players; the owners do not need to vote again.
The sides worked through the weekend and wrapped up the details Monday morning on a final pact that is for 10 years, without an opt-out clause, a person familiar with the deal told the Associated Press.
Teams could start signing draft picks and rookie free agents on Tuesday. Veteran-free agents could be signed on Friday, and training camps for all 32 teams would be open by Sunday.
Owners decided in 2008 to opt out of the league's old labor contract, which expired this March. That's when the owners locked out the players, creating the NFL's first work stoppage since 1987.
The Associated Press contributed to this story