Creator Armando Iannucci first spoke of the censorship after he was informed of it by fans on Twitter.
"I gather the swearing was beeped on Thick of It? Anyone know if that's true," he tweeted. "BBC America tells me nothing."
A BBC America spokesman later confirmed: "BBC America abides by basic cable television common practice in the US in using bleeps to cover profanity in its programmes.
"Bleeps were used during The Thick of It season three premiere on Saturday at 12am."
Iannucci's current political comedy Veep is able to broadcast profanities as HBO is not subject to BBC America's restrictions.
Julia Louis-Dreyfus stars in Veep, which centres around vice president Selina Meyer as she takes on her new position in the White House.
Veep was recently renewed for a second season by HBO after just one episode.
Watch a trailer for Veep below: