The Catechism in Questions & Answers

169. What did Judas Iscariot do after Jesus’ sentencing?

After Jesus had been condemned to death, Judas Iscariot regretted his betrayal and brought the 30 pieces of silver back to the chief priests. These men no longer wanted anything to do with him. He threw the money into the temple, then went out and hanged himself (cf. Matthew 27: 1-5).