The show, starring Poppy Montgomery as a detective who remembers everything, had been canceled to make room for four drama pilots the network had ordered full series for, The Hollywood Reporter reported Friday.
Officials at CBS took to Twitter Friday to let viewers know they changed their mind about the drama.
"Hey #Unforgettable fans. It's official, the series will return to #CBS for summer 2013," the network tweeted.
"Unforgettable" had steady ratings in its 10 p.m. Tuesday slot during its first season, averaging 12.1 million viewers and a 2.5 rating in the key 18 to 49 age range, THR said.