The 2016 season began in February 2016, with United playing Liga MX club, Querétaro, in the quarterfinal series of the 2015–16 CONCACAF Champions League.

In the fall, United went on a regular season surge, which saw the Black-and-Red win four of their final five games, allowing them to finish fourth in the Eastern Conference and tied for ninth overall.

United's top scorers during the campaign came from newcomers, both of whom had previous played for MLS franchises: Lamar Neagle from Seattle Sounders FC lead the team with 10 goals across all competitions.

The team traded winger Chris Pontius to the Philadelphia Union, they were unable to reach a new agreement with long-time central midfielder Perry Kitchen.

The team used the pick to Select another midfielder, from 2015 NCAA Division I Men's Soccer Championship Game runner-up Clemson University, Paul Clowes.

The team filled the holding mid slot by trading for MLS veteran Marcelo Sarvas, and got a bit of an unexpected boost when the name of a former acquisition target, Boca Junior's midfielder/forward Luciano Acosta suddenly showed up on the transfer rumor wires.

As preseason continued, the team released Conor Doyle to make way for a trialist from USL side Pittsburgh Riverhounds, winger Rob Vincent.

In its 2016 Major League Soccer season opener, D.C. United started off well with a goal by newcomer Lamar Neagle to take a 1-0 lead over the LA Galaxy in the fifth minute.

As D.C. traveled to Foxboro to face the New England Revolution, Andrew Dykstra was forced to sit out with back spasms, and Fabian Espindola was nursing a tender hamstring.

Dykstra later turned out to need back surgery that would sideline him for 10–12 weeks,[1] joining Hamid on the injury list and leaving the netminding duties up to sophomore keeper Travis Worra and the recently signed Horton.

DC hoped to bounce back in their home opener against the Colorado Rapids, but the team only managed a 1-1 draw thanks to Espindola coming off the bench and chipping a rebound into the net in the 80th minute.

D.C. United announced the signing of veteran MLS keeper Tally Hall to shore up their increasingly-wounded goalkeeping corps, which turned out to be a prescient move as Horton suffered a concussion during training and would not be ready in time for the next match.

Despite getting an early lead when Nyarko headed in a spectacular cross by Neagle, and seeing several miraculous saves from Worra, a mistake by Espindola late in the game quickly led to a game-tying goal by Adam Jahn.

On April 20, the MLS Disciplinary Committee suddenly announced that they would suspend manager Ben Olsen and fine him $500 for stepping onto the field during the Toronto match.

United failed to build on the momentum of the Kansas City win, suffering a crushing 0-2 home loss to Seattle, on late goals by rookie Jordan Morris and Joevin Jones.

When MLS league action resumed, United claimed 4 points in their final 2 matches of the month, including a dreary 0-0 draw in Houston that produced no excitement until stoppage time, when Bill Hamid was forced into two spectacular reaction saves.

United seemed resigned to another road loss at Rio Tinto Stadium until Jeffrey scored a header on a stoppage time corner kick to gain the surprise point.

That result, however, seemed a distant memory the next week, when United traveled to the Philadelphia Union, and suffered the team's worst loss to that franchise, a 3-0 drubbing with 2 first-half penalty kick goals and a second yellow-card ejection for Opare.

That card was rescinded later by the Disciplinary Committee, but United was able to press the man advantage and gained a point when late substitute Fabian Espindola pounced on a loose ball and shot it past the reach of the Crew goalie.

The visitors took the lead when Acosta was dispossessed as he tried to dribble out of the defensive end and former United star Chris Pontius continued a remarkable renaissance in his first season away from D.C. and put the Union ahead.

The team doubled that lead in the 29th minute, just before a scheduled heat break, when Acosta finished a chance in front of goal, set up by a nifty chipped pass from Mullins.

Thanks to the usual heroics by Hamid, the team held on for a 2-0 shutout win that lifted United ahead of New England and at least temporarily holding the sixth and final postseason spot in the East.

Despite a pre-game shower during warm-ups and with inclement weather approaching, the teams kicked off on time, but the game was stopped just shy of the 8:00 mark, because a powerful storm was about to settle over RFK.

NYRB punished the home team's mistakes when Bradley Wright-Phillips finished off a play that opened up when Franklin whiffed on an attempted clearance due to poor footing.

With a mid-week trip to Montreal looming, United were clinging to the final post-season slot, holding a tiebreaker edge over Orlando City SC.

Then, in the 5th minute of stoppage time, a loose ball in the box came to Neagle for an easy tap-in, and United emerged with a shocking draw against the run of play.

However, the Fire responded quickly as Luke Mishu, playing for the injured Franklin, lost his mark on a corner kick and surrendered a header for goal.

The 3-1 win clinched a postseason spot for United and left them a point ahead of Montreal in the race for 4th place and a home-field advantage in the play-in game.

D.C. closed out the regular season in Orlando knowing that they would be hosting the play-in round match four days later so long as the Montreal Impact did not win at New England, so it probably should not have surprised anyone that Coach Olsen started a line-up made of entirely of reserves and a few players returning from lengthy injury spells.

D.C. did manage to make the scoreline more respectable in the closing moments, as Neagle headed in a Nyarko cross for a goal in the 90th minute and Kemp scored unassisted in stoppage time with a screamer inside the post from 25 yards.