The Catechism in Questions & Answers

644. With what words is the forgiveness of sins proclaimed?

The Apostles proclaim the forgiveness of sins with a direct reference to Jesus Christ: “I proclaim unto you the glad tidings: in the name of our Lord Jesus Christ, the Son of the living God, your sins are forgiven. The peace of the Risen One be with you! Amen.”
The priestly ministers proclaim the forgiveness of sins with reference to the Apostle ministry: “In the commission of my sender, the Apostle, I proclaim unto you the glad tidings: in the name of our Lord Jesus Christ, the Son of the living God, your sins are forgiven. The peace of the Risen One abide with you. Amen.”

Priestly ministers: see Questions 415., 508., 661.