Christie made the announcement earlier on a call with his campaign. He staked his hopes on New Hampshire, but finished sixth on Tuesday night with just 7% of the vote.
"Today, I leave the race without an ounce of regret," Christie wrote on Facebook.
The decision marks a sudden end for someone once seen as a potential front-runner. In the wake of the 2012 election, Christie appeared poised for a strong bid for the Republican nomination -- he won a second term as the Republican governor of a blue state and led the Republican Governors Association, giving him a perch to travel the nation fundraising for other Republicans and building his stature.
But shortly after he was elected to his second term in November 2013, he was engulfed by the "Bridgegate" scandal. Emails and texts from top aides show they requested that two lanes onto the George Washington Bridge
be shut down in September 2013, causing massive traffic jams in Fort Lee, New Jersey, after the town's Democratic mayor declined to endorse Christie's re-election.
A federal investigation determined that Christie had no knowledge of the decision to close the lanes, but the political damage was real. By the time he announced his bid at the end of June 2015, the damage from "Bridgegate" had many wondering whether his campaign
was dead from the start.
But Donald Trump's ascendance over the summer quickly sucked the air out of the room for almost any other political narrative, including "Bridgegate."
Christie, meanwhile, embarked on a tenacious strategy focused almost exclusively on winning New Hampshire. By February 8, he had made 190 stops in New Hampshire, more than any other candidate, according to NECN's candidate tracker
That attention to the first-in-the-nation primary state paid off in December, when Christie won the endorsement of the New Hampshire Union Leader. At the same time, he won 2016's somewhat informal mark of arrival — withering attacks from Trump.
Christie often talked of his personal experience on September 11, 2001, waiting anxiously for his wife to return from lower Manhattan. But after the terrorist attacks in Paris and San Bernardino last year, Christie began telling that personal story more, as well as playing up his experience as a federal prosecutor immediately after September 11.
But he still faced fallout among the Republican primary electorate after his warm welcoming of Obama in October 2012, after Hurricane Sandy walloped his state.
When pollster Frank Luntz replayed clips of the meeting for a focus group in New Hampshire, after the first Republican debate, Republicans in the room said they were still unhappy, three years later.
Throughout the race, Christie stood out for his blunt statements and a seeming inability to sugarcoat his assessments of the competition -- and by February, Marco Rubio was bearing the brunt of it.
As the field moved from Iowa to New Hampshire, Rubio became the star following a breakout performance in the caucuses. But many candidates, including Christie, Jeb Bush and John Kasich had pinned their hopes on New Hampshire.
Christie took to mocking Rubio's scripted style and work in Washington, calling him the "boy in the bubble" because, according to Christie, the Florida senator was too protected by staff.
In the eighth Republican debate, just a few days before the New Hampshire primary, it was Christie who knocked the air out of Rubio -- and claimed his putdown as enough to earn a ticket out of New Hampshire.
"I think the whole race changed last night. Because you know there was a march among the chattering class to anoint Sen. Rubio," Christie told Jake Tapper on CNN's "State of the Union"
one day after the debate. "I think after last night, that's over. So I think there could be four or five tickets out of New Hampshire because the race is so unsettled now."