The actor, who plays Barney in the hit sitcom, wed partner David in front of friends and family at a private Italian ceremony on Saturday, 6 September.
A thrilled Neil confirmed the news via Twitter, saying: "Guess what? David and I got married over the weekend. In Italy. Yup, we put the 'n' and 'd' in 'husband'."
He added a sweet photo taken of them during the ceremony.
A statement released to People said: "We happily confirm that Neil Patrick Harris and David Burtka were married in Italy in an intimate ceremony surrounded by their close friends and family."
The ceremony was officiated by close friend Pam Fryman, who directed many episodes of How I Met Your Mother, while Sir Elton John performed.
Neil, 41, and David, 39, have been together for around ten years and are parents to three-year-old twins Harper and Gideon, born via surrogate.
They revealed their plans to marry back in 2011 when gay marriage was legalised in their New York home stage. At the time, Neil revealed that he and David had proposed to each other more than five years before but had had been "waiting for an available date."
Congrats to Neil and David!
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