Arenas drove up to his house in the Virginia suburbs of Washington in a tan Mercedes SUV at about 8:30 a.m.
He tried several times to punch the combination on the keypad to enter his gated driveway. After several failed attempts, he muttered "Alrighty," got out of his car and yelled toward the house for help. A woman inside the house yelled out the code. Arenas punched it in and drove into his driveway.
Arenas was asked several times for comment about his stay at the halfway house. Each time he shrugged and indicated he had nothing to say.
A few minutes later, he re-emerged in a long-sleeve black T-shirt with a hood pulled low over his forehead. He hopped into a white Range Rover and drove off.
Arenas pleaded guilty to felony gun possession in the District of Columbia in January and was sentenced in March to a month in the halfway house. His sentence also includes two years of probation, a $5,000 fine and 400 hours of community service that can't be performed at basketball clinics.
His sentence started April 9 with two days in jail before he was moved to the halfway house in the Maryland suburbs of Washington. He was allowed to leave the facility during the day. A fan tweeted about seeing him at a local grocery store and posted a picture of him posing near the bottled tea.
Arenas' sentence called for 30 days at the facility, but he was released slightly early because the Federal Bureau of Prisons doesn't release offenders from halfway houses on weekends.
The 28-year-old point guard is now free to resume his basketball career. His NBA suspension expired at the end of the season, and he has four years remaining on a six-year, $111 million contract he signed with the Wizards in the summer of 2008.
The Wizards could have attempted to trade Arenas or void the remainder of his contract, but president Ernie Grunfeld has said definitively that the team's marquee player will be welcome back next season. It's possible that approach will change after Ted Leonsis completes his purchase of the team in the coming weeks, but the size of the contract would make a trade difficult, and the players' union would vigorously fight any attempt to void it.
Arenas will now be transferred to the supervision of the Virginia Department of Corrections because he is a Virginia resident. Department spokesman Larry Traylor said Arenas will have to report to the Fairfax County Office of Probation and Parole.
Offenders on probation must report any arrests, including traffic tickets, and need permission to travel outside Virginia, according to information on the county website. Arenas is also prohibited from owning or carrying firearms during his sentence.
Arenas began his 400 hours of community service while at the halfway house. His second year of probation may be unsupervised if he abides by all of its conditions.
Arenas got into trouble when he brought four guns to the Verizon Center locker room in December in what he said was an attempt to play a prank on teammate Javaris Crittenton. The two players had argued over a card game on the team plane two days earlier.
Crittenton also had a gun in the locker room that day. He eventually pleaded guilty to misdemeanor firearms possession and received one year of unsupervised probation.
Arenas' sudden downfall derailed the Wizards' season. The team finished 26-56 and traded longtime regulars Antawn Jamison, Caron Butler and Brendan Haywood. Arenas will have to rebuild his image as Washington rebuilds its team -- the player long known as "Agent Zero" has already said he's changing his jersey number from zero to six next season.
Even while in the halfway house, Arenas found himself with more gun problems. A Beverly Hills company is suing him for more than $70,000, saying it has been storing five Beretta pistols he bought in 2006 and never picked up.