Perabo, who plays CIA agent Annie Walker on the show, married Kay, who works with her on USA Network TV series, in Manhattan, a source confirmed to Usmagazine.
After trading vows, they celebrated with family and friends at a reception where they were entertained by a New Orleans style jazz band.
The 37-year-old actress got engaged to Kay last September.
Piper’s breakthrough role came in 2000 as Violet Stanford in Coyote Ugly. She went on to have roles in Cheaper by The Dozen, Prestige and Looper.
She has starred as Agent Walker in the crime drama for the last four years, even winning her a Golden Globe nomination in 2011.
As for Kay, the native of New Zealand has previously been linked to Desperate Housewives star Teri Hatcher.