Discover pocket envelopes in C4 (324 × 229 mm) for flat A4, plus C5 and C6, with white, manilla and colour choices. Pocket envelopes open on the short edge to keep documents upright and easy to file, making them perfect for certificates, brochures, catalogues and reports. Pick window or plain formats with gummed, self seal or peel & seal closures, and select heavier gsm for extra opacity and strength. Recycled papers help meet sustainability goals, while bulk and pallet pricing keeps unit costs low for regular mailings. Quick filters let you refine by size, seal and window position, and we offer fast dispatch across the UK with free delivery on orders £50+. When extra protection or capacity is needed, see our board back and expandable gusset styles.