Custom Square Envelopes

Paper Weights, Colours and Flap Styles

Envelope paper usually runs from 100 to 140 gsm. Lighter stock folds crisply and keeps postage weight down, while heavier stock feels more premium and hides the card's design through the paper, which matters for dark or busy card artwork. Coloured, white, ivory and kraft papers are all available, and we can print a solid colour over white if you need an exact brand shade.

Flaps can be a straight wallet flap, a pointed diamond flap or a rounded flap. Pointed flaps feel traditional and suit wedding stationery. Straight flaps look clean and contemporary and leave a wider area for a printed logo or return address. Choose between gummed flaps you moisten and peel-and-seal strips, which are quicker for large mail-outs. p1 Textured and kraft stocks are shown on our invitation envelopes page.

What You Can Print on Square Envelopes

The front can carry a logo in the corner, a return address, or a printed panel for a handwritten name. The back flap is the most common spot for branding because it is the last thing the recipient sees before opening. Printing inside the envelope, such as a pattern liner effect, is popular with stationers who want a reveal when the flap lifts.

Keep in mind that the address area needs to stay readable for Royal Mail sorting. Leave a clear, pale space on the front for the address and stamp, and keep heavy patterns to the flap, the back or the inside. p1 Monogram and foil options are compared in the guide to print and finish options.

Matching Envelopes Across a Card Range

Card designers rarely sell one card. If your range spans birthdays, sympathy, new baby and thank-you designs, the envelopes can either stay the same across everything or shift colour to suit each theme. A single envelope colour is simpler to stock and cheaper to print in one longer run. A small palette of three or four colours, each picking up a shade from the card fronts, looks more hand-picked on a shelf and helps customers pair cards quickly.

Another approach is one envelope colour with a different inside print per collection. The outside stays consistent for stock control, while the inside pattern ties each envelope to its card. This works especially well for wedding suites, where the invitation, RSVP and thank-you cards each get their own envelope size but share a liner pattern.

Whichever way you go, order the envelopes with the card artwork in front of you. Hold the proof against a printed card so you can judge whether the colours sit well together under normal shop lighting. p2 Christening ranges often use a cream envelope with our printed christening invitations.

Packing, Posting and Selling Square Cards

Retail cards are usually sold with the envelope tucked behind the card inside a clear cello bag. Square envelopes make this tidy because the card and envelope line up edge to edge, with no awkward overhang. If you sell online, consider sending each card with the envelope already inside a hard-backed mailer so the corners arrive square.

For trade orders to shops, pack cards and envelopes in matched bundles of six or twelve per design. Shop owners appreciate not having to sort envelopes by size, and it reduces the chance of a mismatched pair going out to a customer.

Square envelopes are fine to post in the UK, but they can be treated differently from standard letters depending on their size, thickness and weight, so check current Royal Mail guidance for your exact envelope before a big mail-out. Larger squares often fall into a different price band than smaller ones, which is worth knowing if you sell cards by post.

If you are mailing to customers, a slightly heavier paper and a peel-and-seal flap reduce the chance of corners being crushed or flaps opening in transit.

A simple habit that helps: weigh one finished card in its envelope on a kitchen scale before you buy postage in bulk, since a heavier envelope stock or an added insert can tip it into the next band. p4 Cards sold in sets can be banded with a printed belly band instead of a bag.

Fold the Proof Round One of Your Cards

Square envelopes are cut to the card, so the card is what we need to know. Measure the folded card, say whether it is flat or layered with ribbon or a wax seal, and tell us the card stock weight; a thick card wants 5 mm of clearance rather than 3. If you sell two card sizes, order two envelope sizes in the same job rather than forcing both into one.

Pick the paper weight from the card artwork: a dark or busy design shows through 100 gsm, so go heavier or ask for a printed interior. Decide the flap and the closure, then send the logo for the flap. The custom quote arrives by email within one working day, from £0.25 an envelope, with the minimum set per job.

When the free proof arrives, print it at full size, fold it round a real card and check the fit and the colour under shop lighting before you approve it. Production takes 4 to 7 working days after that and the envelopes reach UK mainland addresses by free tracked delivery. Card makers launching a baby range usually add square baby shower invitations in the same stock.