In an apparatus for inserting a postal item into an envelope, the envelope is fed with its flap fold trailing its envelope body and its flap along a flap opener. A free flap opener edge enters between the flap and the envelope body until the flap fold abuts the free flap opener edge. While holding the flap against the flap opener, the flap is pivoted relative to the envelope body about the flap fold to an open position and subsequently the postal item is inserted into the envelope body. An apparatus for carrying such a method is also described.