An inserting system has an envelope feeding station, an enclosure feeding station, and a folding station having a first and a second folding nip for folding documents. Documents are inserted into envelopes, which are held in an inserting position. Envelopes are transported through an envelope transport path from their feeding station to the inserting position, and enclosures are transported through an enclosure transport path from their feeding station to the inserting position. The enclosure transport path comprises a diverter, a first enclosure transport path part between the enclosure feeding station and the diverter and a second enclosure transport path part between the diverter and the inserting position. The second enclosure transport path part passes through the first and the second folding nip. A third enclosure transport path part is present between the diverter and the inserting position and bypasses the first folding nip and passes through the second folding nip.