How to find a prospect's postal address in the UK

First, the four addresses

Before you go looking, know what you are looking for. This is the part that quietly ruins most first campaigns, because the easiest address to find is usually the wrong one.

Address	What it is	Post here?
Registered office	The statutory address at Companies House, where legal notices go. For a large number of small UK companies it is their accountant or a formation agent.	Only when it matches the trading address
Trading address	Where the business actually operates	Yes
Site or branch	The specific office your contact sits in	Better, when you can identify it
Director's service address	A published contact address for a named director, often their home	No

You can spot a formation agent quickly. The address is a suite or floor number, a search of that postcode at Companies House returns dozens of unrelated businesses, and the company's own website gives a completely different address for getting in touch. Post there and your letter is opened by an accountant who has never heard of your prospect.

The method, in the order that wastes least time

Read the company's own website first. Footer, contact page, or the terms and conditions, which nearly always carry a real address. Highest quality source, and the one most people skip because it feels too obvious.
Work out which building your person is in. Their LinkedIn location, the dialling code on an email signature, a regional page on the site. For any business with more than one site this single step matters more than everything else here.
Use Companies House as a cross check, not a starting point. Authoritative about the legal entity, frequently useless about where humans sit.
Validate the postcode. Run it against the Royal Mail address file so the format is right and the delivery point exists. A surprising share of returned mail is a formatting error rather than a wrong building.
Screen out the addresses that need a different decision. Formation agents, virtual offices, and homes. Our page on sole traders and home addresses covers that last one, because it is a judgement rather than a lookup.
Address it to a person and a role. The name gets it to the desk. The job title saves you when they have moved on.

On buying a list. Buying is not illegal, but you inherit the seller's sourcing the moment the file lands. Ask where the data came from, when it was collected, and what people were told at the time. Vagueness in the answer becomes your vagueness when someone asks you the same question.

What accuracy to expect, honestly

No source is clean. A company's own website is the most reliable and the most out of date, because nobody edits the footer when they move. Companies House is precise about the entity and silent about the people. Anyone promising you a perfect B2B address file is selling something. The workable standard is to check before you send rather than discover afterwards, and to treat a small return rate as the cost of doing business rather than a failure.

Where the software helps

Rockkt does this from a LinkedIn profile: finds a deliverable address, validates it, and flags the cases a human should look at, such as an agent address or a residential one. One credit is one fully worked prospect and it comes off your allowance the moment the search runs, so the number in the app is always the truth rather than an estimate.

Sam Hill

Sam works at Rockkt, a UK company that builds software for sending physical post to sales prospects, so address data is most of the working week. Read how we write these guides, including where AI comes into it and what we will not publish.

How to find a prospect's postal address, and which of their addresses to use

First, the four addresses

The method, in the order that wastes least time

What accuracy to expect, honestly

Where the software helps

From a LinkedIn profile to an envelope