How to Address an Envelope in the UK: Royal Mail Guidelines

Royal Mail's automated sorting system scans millions of envelopes every day using optical character recognition. Getting the address format right means the machine reads it correctly on the first pass, avoiding manual handling and potential delays. This guide covers everything you need to write a correctly addressed envelope for UK delivery.

The standard UK address format

A correctly formatted UK address on an envelope looks like this:

Mr James Taylor
14 Oak Street
Birmingham
West Midlands
B1 1BB

Each element on its own line, in this order:

1. Recipient name: the person or organisation the letter is addressed to
2. House or building number and street name
3. Town or city
4. County (optional, but good practice)
5. Postcode (always last, always in capital letters)

Where to position the address on the envelope

The address should be written or printed in the lower centre of the front of the envelope. Royal Mail's sorting machines are set up to read addresses in this location. An address written too close to the top of the envelope or pushed to one side may not be captured automatically.

Leave a clear margin around the address block. Avoid writing anything else in the lower portion of the envelope front, such as decorative borders or personal messages, as these can interfere with machine reading.

The postcode

The postcode is the most critical element for automated sorting. Always write it in capital letters, on its own line, at the very end of the address. Write it in the standard two-part format with a space between the outward and inward codes, for example: SW1A 2AA, not SW1A2AA.

Never put the postcode on the same line as the town. Royal Mail's systems are set up to read it as a standalone line.

The return address

A return address is not required but is strongly recommended. If Royal Mail cannot deliver the letter, a return address allows them to return it to you rather than sending it to the national returns centre.

Put the return address in the top left corner of the front of the envelope, or on the back flap. Keep it noticeably smaller than the main recipient address, or label it clearly as "Return address" or "From:", so it cannot be confused with the delivery address.

Never write a return address in a position that could be mistaken for the main delivery address.

Addressing a flat or apartment

For flats and apartments, include the flat number on the first line and the building name or street number on the second line:

Ms Sarah Jones
Flat 7
Elm Court
22 Station Road
Leeds
LS1 4BT

Addressing a company or organisation

When writing to a company, put the company name after the individual recipient's name (if there is one), or use the company name alone on the first line:

Mr D Patel
Accounts Department
Acme Ltd
100 Business Park
Manchester
M1 2AB

Common mistakes to avoid

• Postcode in the wrong place: The postcode must be the last line of the address, on its own line.
• Lowercase postcode: Always write postcodes in capital letters.
• Abbreviating the street name inconsistently: Write "Street", "Road", "Lane" in full or use a consistent abbreviation. The automated reader handles both.
• Missing house number: If the property has a number and a name, include both. The number is more reliably sorted than the name alone.
• Smudged or illegible writing: If the address cannot be read by the machine, it goes to manual sorting, which takes longer. Print addresses if your handwriting is not clear.

Addressing letters without touching an envelope

When you send a letter through an online letter service, you type the recipient's address into a form and the service handles addressing, printing, folding and sealing. The address is printed in the correct position on a windowed envelope, removing the risk of formatting errors entirely.

Write and send your letter online for same-day despatch via Royal Mail, from £2.99. No envelope, no stamps, no Post Office visit.