How to build a B2B call list by trade and town

1. Why build your own list

Bought data is often stale, national, and used by everyone else who bought it. A list you build from public listings is local, current and specific to what you sell. You know why each business is on it, which also makes it easier to explain where you got their details if they ask, something UK GDPR expects you to be able to do.

2. Pick the trade and the patch

Start with a narrow search, not "all businesses near me". Write down:

The trades that buy what you sell. A commercial cleaner might pick offices, dental practices, nurseries and gyms. An EPOS reseller might pick independent cafés and restaurants, and skip chains.
The towns you can serve, and how far you'll travel.
Who to leave out: competitors, one-person businesses if they're too small for you, or national chains whose buying is done at head office.
The signals that make a business a good fit. For a web agency, a slow or missing website. For a signage firm, a business that's just opened.

"Dentists in Chelmsford" is a list. "Businesses in Essex" isn't.

3. Find the businesses (Google Maps)

Google Maps is the most complete free directory of local, trading businesses, and listings usually include a phone number, website, opening hours, rating and review count. Search for the trade and town, then work through the results, noting for each business:

name, address and main phone number;
website (or the lack of one);
rating and number of reviews;
whether the listing says it's permanently closed.

Doing this by hand is slow. Check the terms of any tool that extracts listings for you, and don't copy more than you need.

4. Add the decision maker (Companies House)

If a business is a limited company, its directors are on the public register at Companies House, which is free to search. That gives you a name to ask for, which changes the first ten seconds of a call. "Can I speak to Jane Patel?" gets further than "Can I speak to whoever deals with your cleaning?".

Search by company name, and match on the registered or trading address.
Check the company is active, and use current directors, not resigned ones.
You can also search the register by industry (SIC code) and area to find companies Maps missed. Those records don't include phone numbers, so you'll need to find one (for example a Maps match) before you can call.

Sole traders and most partnerships aren't on the register, so their records will only have the business name. That's also a clue for screening: they're usually on the TPS, not the CTPS, if registered.

5. Clean and de-duplicate

Before anyone dials, remove closed businesses, duplicates (the same phone number under two names is common), businesses you already work with, and anyone on your own do-not-call list. Put each number in one consistent format so duplicates are easy to spot.

6. Screen before you call

Every number on a B2B list should be screened against both the TPS and the CTPS before you make a live marketing call, unless that business has told you they're happy to hear from you. Keep the date of each check and screen again regularly. UK cold calling rules explained →

7. Prioritise the list

Not every lead deserves the first call. Give each a simple grade using what you collected:

Signal	Why it matters (example)
Limited company with named directors	You can ask for a decision maker by name.
Many reviews, good rating	An established, busy business, likely to have budget.
Slow or no website	A direct reason to call, if you sell websites or marketing.
Several sites	A bigger contract, for cleaning or recruitment.
Recently opened	Still buying signage, payments or services.

Call the A grades first, while your reps are fresh. These are examples; tune the signals to what you sell.

8. Split it between reps

Two reps ringing the same business on the same day is the fastest way to look disorganised. Assign leads to reps, by area or by trade, and log every outcome on the lead so a call back is never missed.

9. Doing it in Patchline

Patchline's lead finder does steps 3 to 7 for you. Search by trade and town (for example "dentists in Chelmsford") with rating and website filters; closed businesses and duplicates are skipped, and Companies House director names are added for limited companies. A Companies House search by industry and area finds more firms, matched to a phone number before they can be called. Industry packs pick the trades to search and the scoring for your sector, so a cleaner never gets other cleaners. On Growth and up, leads are scored A, B or C with a plain-English "why this score", and TPS/CTPS screening runs before every dial. Lookups are 200 a month on Starter and 1,000 on Growth. See the cold calling CRM →

10. FAQ

Is it legal to call businesses from Google Maps listings?

Using public listings to find businesses is common, but the PECR rules still apply: screen numbers against the TPS and CTPS, identify yourself on the call and honour opt-outs. Personal data such as a director's name falls under UK GDPR, so have a lawful basis and be ready to say where you got it.

Does Companies House give phone numbers?

No. The register gives company details, the registered office and officers such as directors, but not phone numbers. Match the company to its listing or website to find one.

How big should a list be?

Big enough for a few days of calling per rep, small enough to keep fresh. Build lists per trade and town, and build the next one when it runs low, rather than one huge list that goes stale.

Can I upload a list I already have?

Yes, in most CRMs. In Patchline you can upload CSV or Excel files; uploaded lists still go through screening, and they're your responsibility.

How to build a local B2B call list by trade and town