How To Post A Card In The UK Without It Costing Extra

How to post a card in the UK

Most greetings cards go as a standard Letter. Cards get expensive when they are square, padded, or hold something bulky like a badge or a keyring.

Check the size rules below before you buy the stamp, and always confirm current prices and Christmas last posting dates on the Royal Mail website.

Cards that post as a standard Letter

Flat cards, standard envelopes, no surcharge surprises.

You Old Bastard (Funny Birthday Card) You Old Bastard (Funny Birthday Card) £3.87 Cheeky Wordsearch Valentines Day Card For Him Cheeky Wordsearch Valentines Day Card For Him £3.87 Fifty & Even More Fabulous Than Ever (50th Birthday Card) Fifty & Even More Fabulous Than Ever (50th Birthday Card) £3.87 Cheeky Wordsearch Valentines Day Card For Her Cheeky Wordsearch Valentines Day Card For Her £3.87 I Wish You Looked At Me Like Any Can of Diet Coke Ever (Valentines Day Card) I Wish You Looked At Me Like Any Can of Diet Coke Ever (Valentines Day Card) £3.87 Sixty Looks Pretty Good On You (60th Birthday Card) Sixty Looks Pretty Good On You (60th Birthday Card) £3.87

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What counts as a Letter

  • Up to 24cm long, 16.5cm wide and 5mm thick.
  • Up to 100g in weight.
  • It must be flat - if it will not slide through a slot, it is not a Letter.

When it becomes a Large Letter

  • Anything over 5mm thick, including a card with a badge or a bulky insert.
  • Anything longer than 24cm, which catches a lot of oversized cards.
  • Padded envelopes, even thin ones.

Stamps

  • All ordinary UK stamps are barcoded - old non-barcoded stamps are no longer valid postage.
  • Second class is fine for anything posted a week ahead.
  • First class for anything inside three working days.
  • If you are unsure of the size, take it to a Post Office counter rather than guessing.

How far ahead to post

  • Ordinary card, second class: post five working days before.
  • Ordinary card, first class: post two working days before.
  • Christmas: post well before the published last posting dates, which are earlier than most people expect.
  • Sympathy cards: post the day you write them.

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How to write it so it lands

  • Weigh anything with an insert - badges push cards over 5mm quickly.
  • Buy a book of second class stamps in advance for birthdays.
  • Check Royal Mail for current prices and Christmas dates before a big send.

Where to shop next

Frequently asked questions

Why do square cards cost more?

Square envelopes do not run through automated sorting the same way, so they are often charged at a higher rate. Check at the counter if the card is square.

What happens if I underpay?

The recipient is asked to pay a surcharge before it is released, which is exactly the opposite of a nice surprise.

Are old stamps still usable?

Only barcoded stamps are valid. Old non-barcoded ones had to be swapped through Royal Mail's swap-out scheme.

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