In 2169, people are born genetically engineered with a digital clock on their forearm. When they turn 25 years old, they stop aging and their clock begins counting down from one year;[Note 1] when it reaches zero that person "times out" and dies. Time has become the universal currency; it is used to pay for day-to-day expenses and can be transferred between people or capsules. The country has been divided into "time zones" based on the wealth of the population. The movie focuses on two specific zones: Dayton - a poor manufacturing area where people generally have 24 hours or less on their clock at any given time - and New Greenwich - the wealthiest time zone, where people have enough time on their clock to live for centuries.
Will Salas (Justin Timberlake) is a Dayton factory worker who lives with his mother Rachel (Olivia Wilde). One night at a local bar, he saves the drunken and suicidal Henry Hamilton (Matt Bomer) from an attempted robbery by local thief Fortis and his gang. Hamilton, who is 105 years old, reveals to Will that the truth about time wealth is that there is plenty of time for everyone to live a long life. The people of New Greenwich hoard most of the time for themselves in order to live forever, while constantly increasing the cost of living in poorer districts to keep people dying. Hamilton gives a sleeping Will 116 years of his time, leaving himself with 5 minutes. He then sits on a nearby bridge and times out, falling dead into the water. Will awakens to a message from Hamilton not to waste the time he was given, and rushes to the bridge too late to stop the suicide. Raymond Leon, leader of the police-like Timekeepers, leads the investigation into Hamilton's death, and incorrectly assumes that Will robbed and killed Hamilton.
Will visits his best friend Borel and shares ten years with him, one for each year of their friendship. Will tells Borel that he is going to use the time to move with his mom to New Greenwich. Meanwhile, Rachel uses all but 90 minutes of her time to make a loan payment and finds herself short for bus fare to get home. The uncaring driver forces her to run back to Dayton, but she arrives a few seconds too late for Will to save her and times out in his arms. Will decides to call a car service and head to New Greenwich, where he spends his first night in a suite at a hotel. The next day, he meets time-loaning businessman Philippe Weis and his daughter Sylvia at a local casino. While playing poker with Weis, Will bets all of his time and wins 1,100 years in the hand. Afterward, Sylvia invites him to a party in the Weis mansion. Will buys a car and drives himself to the party, where the Timekeepers quickly apprehend him. Raymond Leon confiscates all but two hours of Will's time, but Will manages to escape with Sylvia as a hostage. En route to Dayton they are ambushed by Fortis and his gang, who take all but thirty minutes of their time. Will attempts to get some time back from Borel, but learns that he used his time to drink himself to death. Sylvia is forced to pawn some jewelry to get time, and Will calls her father to demand a 1,000 year ransom for her. Weis refuses to pay, and Will decides to release Sylvia. She calls her father again from a pay phone, but they are ambushed by Leon, whom Sylvia shoots by accident.
Will and Sylvia decide to team up and begin robbing her father's time banks. A ten-year reward is offered for their capture, which leads Fortis and his gang to hunt them down in a local hotel room. Will shoots the rest of the gang and escapes with Sylvia, after killing Fortis by winning a duel to the death. They realize they cannot steal enough time to effectively change things, as New Greenwich simply raises prices to compensate. They decide on a big score and rob her father's personal vault for one million years. Timekeeper Leon chases them back to Dayton, but is too late to stop them from distributing the stolen time to the poor. Leon chases them to the outskirts of the city where he times out, having forgotten to collect his daily time allotment. Will and Sylvia, each with just over a minute to live, race to Leon's patrol car and Will collects Leon's daily pay. In a scene reminiscent of his mother's death, Will and Sylvia run toward each other with seconds left; this time, he makes it in time to save her.
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.