Shop square envelopes in best-selling 150 × 150 mm and 155 × 155 mm, plus 100, 120, 130 and 140 mm sizes for wedding invitations, greetings cards and premium mailers. Choose premium white, natural manilla or vibrant colours with window-free faces for a clean presentation, and pick gummed, self seal or peel & seal closures. Heavier gsm and ultra-opaque options protect foiled cards and photographs, while recycled and FSC-certified papers support sustainability goals. Use filters to refine by size, colour and seal, and save with box, outer and pallet pricing for regular post. Orders dispatch quickly from our UK warehouse with free UK delivery when you spend £50+. Need more capacity or protection? Pair with gusset or board back styles to keep corners crisp and contents flat.
