Earlier this year, Bell said that she and her fiancé had not set a date because of "mutual laziness."
"I have to unfortunately report that we just haven't gotten it together on a Saturday to get to the courthouse," the House of Lies star said.
"But we have every intention to. We have every intention to. We wanna sign those papers. And I think we just found out that you can do it online now. What if we got married online? Print it out: ‘You guys, married! Married, everybody!' It's just out of laziness that we haven't actually done it yet."
On Thursday, the Hollywood couple followed through, tying the knot in the Beverly Hills County Clerk's office.
Bell, 32, and Shepard, 38, planned to show up, get a marriage license and be on their way. When a court employee offered to marry them in a nearby courtroom, though, they decided it could be their no-fuss wedding.
Bell reportedly teared up during the spontaneous ceremony.
The "Parenthood" actor and "Veronica Mars" actress got engaged in 2009 and welcomed one child, daughter Lincoln, seven months ago. They publicly vowed not to get married until same-sex marriage bans were overturned, however.
"I don't feel appropriate taking advantage of a right that's denied to my [gay and lesbian] friends," Bell said in August 2012. "It's just kind of rude to invite everyone to a party for a rite not everyone can hold."
After the Supreme Court overturned the federal Defense of Marriage Act and dismissed a defense of California's Proposition 8, Bell re-proposed to Shepard on Twitter.
DOMA is dead. Prop 8 is dead. Now let's bring my big, gay marriage to @IMKristenBell to Life!!!!— dax shepard (@daxshepard1) June 26, 2013
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