The actor - who played Xander Harris in the supernatural series - tied the knot with partner Moonda Tee at a ceremony held in Sin City earlier this month.
He announced his happy news via Twitter, showing a picture of the newlyweds standing next to the iconic 'Welcome To Fabulous Las Vegas' sign.
The caption read: "AND WE'RE MARRIED #tilldeathdouspart."
Nicholas and Moonda's wedding came just one week after Nicholas popped the question in a moment he later shared with fans via Twitter.
A picture showed the actor down on one knee as a thrilled looking Moonda accepted... while getting her hair done at the salon.
Congrats to the happy couple!
Last month, Nicholas reunited with his former Buffy co-star Emma Caulfield - Anya - while attending a fan event in Australia. The pair played onscreen lovers until the show's finale.
Stars who married in 2014:
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