How many stamps do wedding invitations need in the UK?

Short answer

Most standard wedding invitations need one stamp, but heavier or larger invitations may need two or more. The number depends on weight, size and thickness. Check at your local Post Office or use the Royal Mail online postage calculator before posting.

The number of stamps your wedding invitations need depends on their weight, size and thickness. A standard A5 or A6 invitation on light card, in a standard envelope, usually needs just one stamp. But if you add extra layers like a belly band, a wax seal, a card insert or a thick envelope, the weight goes up. Once the envelope weighs more than 100g, or is larger than standard letter size, you will need extra postage.

To be safe, take one fully assembled invitation to your local Post Office and ask them to weigh it. They can tell you exactly how many stamps you need. You can also use the Royal Mail online postage calculator, but the rules can change, so checking at the counter is the most reliable option.

Remember that square envelopes are classed as non-standard and often cost more to post. They may need extra stamps even if they are light. Also, if you are adding a wax seal, it can make the envelope lumpy, which may push it into a higher postage band.

For save the dates, thank-you cards or other stationery, the same rules apply. Always weigh and measure each type of mailer separately. It is better to overpay slightly than to have your invitations returned or delayed.