Will Salas is a 28-year-old Dayton. One night at a local bar, he saves a drunken 105-year-old man named Henry Hamilton from an attempted robbery by a gang of "Minutemen" (time-robbing thugs) lead by 75-year-old Fortis. Later that night, in a secret location, Hamilton reveals to Will the truth about time wealth: there is plenty of time for everyone to live a long life. Hamilton explains that the people of New Greenwich hoard most of the time for themselves to live forever, while constantly increasing the cost of living keeps poorer people dying. The next morning, Hamilton transfers 116 years of his time to a sleeping Will, leaving himself with 5 minutes. Will awakes and rushes to a nearby bridge where Hamilton is sitting. Hamilton times out and falls off the bridge. Raymond Leon, leader of the police-like Timekeepers, investigates Hamilton's death, and erroneously assumes that Will played a part in it.
Will visits his best friend Borel, transferring ten years to him, and plans to move with his mother to New Greenwich. After work, Rachel uses all but 90 minutes of her time to pay off a 2-day loan and finds herself short for bus fare to get home since the fare has been increased without notice. Her pleas for help are ignored by the driver and passengers, and she begins running home. Not seeing her at the bus stop, Will also begins running to find her. They see each other, but Rachel times out in Will's arms before they can reach each other.
The following morning, Will heads to New Greenwich and stays in a hotel suite. He visits a local casino and meets 110-year-old time-loaning businessman Philippe Weis and his 27-year-old daughter Sylvia. While playing poker with Weis, Will comes dangerously close to timing out, but eventually wins 1,100 years. Sylvia invites him to a party in the Weis mansion. Will buys a car and drives himself to the party, where the Timekeepers arrest him.
Dismissing Will's claim of innocence, Raymond confiscates all but two hours of his time. Will escapes with Sylvia as hostage and drives back to Dayton. They are ambushed by Fortis' gang, and are left with 30 minutes each. Will visits Borel, but his wife Greta tells him that he has drunk himself to death with nine years left on his clock. Sylvia pawns her jewelry for extra time, and Will calls Weis to demand a 1,000 year ransom. When Weis refuses to pay, Will decides to release Sylvia. She calls Weis from a pay phone, but they are ambushed by Raymond, whom Sylvia shoots by accident.
Will and Sylvia decide to team up and begin robbing Weis' time banks, giving the extra time capsules to the poor. After a ten-year reward is offered for their capture, Fortis' gang tracks them down to a hotel room. Will challenges Fortis to a "time-duel" to the death. Fortis times out and Will shoots the rest of the gang. However, the pair realize they cannot make a significant change, as New Greenwich simply raises prices to compensate for the extra time citizens now have.
They successfully rob Weis' personal vault and obtain the one-million-years capsule. Raymond chases them back to Dayton, but is too late to stop them from distributing the stolen time. After chasing them to the city's outskirts, Raymond reveals that he also came from Dayton and intends to stop other Daytoners from doing the same. However, he realizes too late that he forgot to collect his daily time allotment and times out. Will and Sylvia, each with just over a minute to live, race to Raymond's patrol car. Will collects Raymond's daily share and runs back to Sylvia in a scene reminiscent of his mother's death. This time, he saves her when her clock only has seconds left.
TV reports show factories in Dayton shutting down as everyone has enough time and abandons their jobs to go to New Greenwich. Will and Sylvia continue robbing banks as part of their efforts to crash the system, while the rich attempt to cope with the sudden surge of people infiltrating their zone.