Square Envelopes

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. 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.

Showing 176 products
White Envelope (220 x 220mm)
White Envelope (220 x 220mm)
£0.23 £0.28
On Sale
£0.23 £0.28
White Business 120gsm Peel & Seal Envelope (140 x 140mm)
White Business 120gsm Peel & Seal Envelope (140 x 140mm)
£0.16 £0.20
On Sale
£0.16 £0.20
White Business 100gsm Gummed Envelope (165 x 165mm)
White Business 100gsm Gummed Envelope (165 x 165mm)
£0.16 £0.19
On Sale
£0.16 £0.19
White Business 120gsm Peel & Seal Envelope (185 x 185mm)
White Business 120gsm Peel & Seal Envelope (185 x 185mm)
£0.21 £0.26
On Sale
£0.21 £0.26
Pale Pink Gummed V-Flap 120gsm Envelope (155 x 155mm)
Pale Pink Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.29 £0.35
On Sale
£0.29 £0.35
Gold Coloured Peel & Seal 120gsm Envelope (155 x 155mm)
Gold Coloured Peel & Seal 120gsm Envelope (155 x 155mm)
£0.30
£0.30
White Business 120gsm Peel & Seal Envelope (240 x 240mm)
White Business 120gsm Peel & Seal Envelope (240 x 240mm)
£0.38 £0.46
On Sale
£0.38 £0.46
White Business 120gsm Peel & Seal Envelope (165 x 165mm)
White Business 120gsm Peel & Seal Envelope (165 x 165mm)
£0.20 £0.25
On Sale
£0.20 £0.25
Dark Red Gummed V-Flap 120gsm Envelope (155 x 155mm)
Dark Red Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.35
£0.35
White Business 120gsm Peel & Seal Envelope (120 x 120mm)
White Business 120gsm Peel & Seal Envelope (120 x 120mm)
£0.11 £0.14
On Sale
£0.11 £0.14
Black Coloured Peel & Seal 120gsm Envelope (220 x 220mm)
Black Coloured Peel & Seal 120gsm Envelope (220 x 220mm)
£0.64
£0.64
Cross Mailer Packing Boxes
Cross Mailer Packing Boxes
From £1.19
£1.20
Cherry Red British Made 100gsm Gummed V-Flap Envelope (155 x 155mm)
Cherry Red British Made 100gsm Gummed V-Flap Envelope (155 x 155mm)
£0.16
£0.16
White Business 120gsm Peel & Seal Envelope (200 x 200mm)
White Business 120gsm Peel & Seal Envelope (200 x 200mm)
£0.26
£0.26
Anti-Static Polyethylene Bags
Anti-Static Polyethylene Bags
From £0.16
£0.16
Dark Blue Peel & Seal 120gsm Envelope (155 x 155mm)
Dark Blue Peel & Seal 120gsm Envelope (155 x 155mm)
£0.34 £0.41
On Sale
£0.34 £0.41
Bright Pink Gummed V-Flap 120gsm Envelope (155 x 155mm)
Bright Pink Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.29 £0.35
On Sale
£0.29 £0.35
White Envelope (120 x 120mm)
White Envelope (120 x 120mm)
£0.11
£0.11
CD Window Envelopes
CD Window Envelopes
From £0.11
£0.23 £0.28
Black Coloured Peel & Seal 120gsm Envelope (155 x 155mm)
Black Coloured Peel & Seal 120gsm Envelope (155 x 155mm)
£0.36
£0.36
Ivory Wove 100gsm Gummed V-Flap Greeting Card Envelope (140 x 140mm)
Ivory Wove 100gsm Gummed V-Flap Greeting Card Envelope (140 x 140mm)
£0.30 £0.37
On Sale
£0.30 £0.37
Bright Red Peel & Seal 120gsm Envelope (155 x 155mm)
Bright Red Peel & Seal 120gsm Envelope (155 x 155mm)
£0.34 £0.41
On Sale
£0.34 £0.41
Dark Green Gummed V-Flap 120gsm Envelope (155 x 155mm)
Dark Green Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.29 £0.35
On Sale
£0.29 £0.35
White Business 120gsm Peel & Seal Envelope (170 x 170mm)
White Business 120gsm Peel & Seal Envelope (170 x 170mm)
£0.20 £0.25
On Sale
£0.20 £0.25
White Luxury 180gsm Peel & Seal Envelope (164 x 164mm)
White Luxury 180gsm Peel & Seal Envelope (164 x 164mm)
£0.28
£0.28
Ivory Wove 100gsm Gummed V-Flap Greeting Card Envelope (155 x 155mm)
Ivory Wove 100gsm Gummed V-Flap Greeting Card Envelope (155 x 155mm)
£0.28 £0.34
On Sale
£0.28 £0.34
Ivory Wove 100gsm Gummed V-Flap Greeting Card Envelope (130 x 130mm)
Ivory Wove 100gsm Gummed V-Flap Greeting Card Envelope (130 x 130mm)
£0.24 £0.29
On Sale
£0.24 £0.29
Pale Pink Peel & Seal 120gsm Envelope (155 x 155mm)
Pale Pink Peel & Seal 120gsm Envelope (155 x 155mm)
£0.34 £0.41
On Sale
£0.34 £0.41
Black Coloured Peel & Seal 120gsm Envelope (170 x 170mm)
Black Coloured Peel & Seal 120gsm Envelope (170 x 170mm)
£0.25
£0.25
Dark Yellow Peel & Seal 120gsm Envelope (155 x 155mm)
Dark Yellow Peel & Seal 120gsm Envelope (155 x 155mm)
£0.34 £0.41
On Sale
£0.34 £0.41
White Luxury 180gsm Peel & Seal Envelope (155 x 155mm)
White Luxury 180gsm Peel & Seal Envelope (155 x 155mm)
£0.25
£0.25
Bright Blue Gummed V-Flap 120gsm Envelope (155 x 155mm)
Bright Blue Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.25 £0.30
On Sale
£0.25 £0.30
Dark Blue Gummed V-Flap 120gsm Envelope (130 x 130mm)
Dark Blue Gummed V-Flap 120gsm Envelope (130 x 130mm)
£0.20
£0.20
White Business 120gsm Gummed Envelope (170 x 170mm)
White Business 120gsm Gummed Envelope (170 x 170mm)
£0.16
£0.16
Pale Grey Peel & Seal 120gsm Envelope (155 x 155mm)
Pale Grey Peel & Seal 120gsm Envelope (155 x 155mm)
£0.25
£0.25
Mid Green Peel & Seal 120gsm Envelope (155 x 155mm)
Mid Green Peel & Seal 120gsm Envelope (155 x 155mm)
£0.34 £0.41
On Sale
£0.34 £0.41
Bright Pink Peel & Seal 120gsm Envelope (155 x 155mm)
Bright Pink Peel & Seal 120gsm Envelope (155 x 155mm)
£0.34 £0.41
On Sale
£0.34 £0.41
Dark Red Peel & Seal 120gsm Envelope (155 x 155mm)
Dark Red Peel & Seal 120gsm Envelope (155 x 155mm)
£0.41
£0.41
White Hammer 100gsm Gummed V-Flap Envelope (155 x 155mm)
White Hammer 100gsm Gummed V-Flap Envelope (155 x 155mm)
£0.28 £0.34
On Sale
£0.28 £0.34
Bright Blue Peel & Seal 120gsm Envelope (155 x 155mm)
Bright Blue Peel & Seal 120gsm Envelope (155 x 155mm)
£0.33 £0.40
On Sale
£0.33 £0.40
Bright Red Gummed V-Flap 120gsm Envelope (130 x 130mm)
Bright Red Gummed V-Flap 120gsm Envelope (130 x 130mm)
£0.20 £0.25
On Sale
£0.20 £0.25
Tuck Flap Envelopes
Tuck Flap Envelopes
From £0.30
£0.67
Pale Blue Envelope (155 x 155mm)
Pale Blue Envelope (155 x 155mm)
£0.34 £0.41
On Sale
£0.34 £0.41
Purple Gummed V-Flap 120gsm Envelope (155 x 155mm)
Purple Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.29 £0.35
On Sale
£0.29 £0.35
Mid Green Gummed V-Flap 120gsm Envelope (155 x 155mm)
Mid Green Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.29 £0.35
On Sale
£0.29 £0.35
Black Gummed V-Flap 120gsm Envelope (155 x 155mm)
Black Gummed V-Flap 120gsm Envelope (155 x 155mm)
£0.35
£0.35
White Luxury 180gsm Peel & Seal Envelope (125 x 125mm)
White Luxury 180gsm Peel & Seal Envelope (125 x 125mm)
£0.20
£0.20
Black Coloured Peel & Seal 120gsm Envelope (100 x 100mm)
Black Coloured Peel & Seal 120gsm Envelope (100 x 100mm)
£0.29
£0.29