A device for inserting sheets into an envelope, comprising: a) a holding device for supporting the envelope during insertion of the sheets into the envelope, when a support portion of the holding device is inserted into the envelope in between a front side of the envelope and a back side of the envelope; b) a feed device for feeding the envelope to the holding device; and c) wherein the support portion of the holding device has a fixed orientation and position relative to the feed device and maintains this fixed orientation during feeding of the envelope, insertion of the sheets and removing of the envelope respectively; characterized in that said device further comprises: d) a mechanism for preparing the envelope for accommodating the support portion of the holding device, the mechanism being arranged upstream of the holding device and comprising a first interaction device, acting onto the envelope in a first direction during feeding of the envelope; a second interaction device arranged downstream of the first interaction device, acting onto the envelope in a second direction during feeding of the envelope, the second direction being essentially opposite to the first direction; wherein the second interaction device comprises at least one cam on a rotatable shaft, wherein by rotation of the shaft the at least one cam may be brought into an interaction position, where the cam interacts with the envelope, and into an inactive position, where the cam does not interact with the envelope. a) a holding device for supporting the envelope during insertion of the sheets into the envelope, when a support portion of the holding device is inserted into the envelope in between a front side of the envelope and a back side of the envelope; b) a feed device for feeding the envelope to the holding device; and c) wherein the support portion of the holding device has a fixed orientation and position relative to the feed device and maintains this fixed orientation during feeding of the envelope, insertion of the sheets and removing of the envelope respectively; characterized in that said device further comprises: d) a mechanism for preparing the envelope for accommodating the support portion of the holding device, the mechanism being arranged upstream of the holding device and comprising a first interaction device, acting onto the envelope in a first direction during feeding of the envelope; a second interaction device arranged downstream of the first interaction device, acting onto the envelope in a second direction during feeding of the envelope, the second direction being essentially opposite to the first direction; wherein the second interaction device comprises at least one cam on a rotatable shaft, wherein by rotation of the shaft the at least one cam may be brought into an interaction position, where the cam interacts with the envelope, and into an inactive position, where the cam does not interact with the envelope. a first interaction device, acting onto the envelope in a first direction during feeding of the envelope; a second interaction device arranged downstream of the first interaction device, acting onto the envelope in a second direction during feeding of the envelope, the second direction being essentially opposite to the first direction; wherein the second interaction device comprises at least one cam on a rotatable shaft, wherein by rotation of the shaft the at least one cam may be brought into an interaction position, where the cam interacts with the envelope, and into an inactive position, where the cam does not interact with the envelope.