B2B email lists UK: buy one, build one, or generate one?
Every UK list broker promises fifty thousand decision makers. Here is what buying actually gets you, what building from the public record costs in time, and when generating a verified list on demand beats both.
Search for a UK B2B email list and you will meet three kinds of seller. List brokers with a spreadsheet of "50,000 decision makers". Database platforms with a subscription and a download button. And tools like ours that generate the list from the public record while you watch. This guide is honest about all three, including where each goes wrong. It is written by the team behind the third kind, so read the recommendation knowing where we stand.
The three ways to get a UK B2B email list
- Buy a ready-made list. A broker or database sells you rows: name, company, email, sometimes a phone number. Fast, and it feels cheap per record.
- Build one yourself from the public record. Companies House lists every UK company for free, with sector, location, age and filing history. You do the finding and checking by hand.
- Generate a verified list on demand. Software runs the same public-record search, then finds and verifies each company's website and email before you pay for the row. This is what Leadistry does.
Most buyers never separate the three, which is how a telemarketing CSV gets judged against a live data pipeline. Pick the model first, then the vendor.
What buying a list actually gets you
Speed, mostly. The CSV arrives today. The problems arrive over the following month.
The rows are old. People change jobs, companies dissolve, mailboxes are retired. A list is a photograph of a moment that has already passed, and brokers rarely tell you when the photograph was taken. The public record changes every single morning: companies incorporate, move, appoint directors and shut down daily, which is why a recurring search beats a snapshot.
The bounce rate is yours now. When we tested one well-known budget database, 4.2% of its addresses bounced. Anything over 2% we treat as a fire: mailbox providers read a high bounce rate as a spam signal and start filing everything you send, including to good addresses, into junk. A cheap list can quietly cost you the domain you send from. Our email warm-up guide explains how slowly that reputation rebuilds.
The legal duties transfer to you. Buying data does not buy lawfulness. The moment the list is yours, you are the controller: you need a lawful basis, a legitimate interests assessment, and an answer for the person who asks "where did you get my details". The ICO has fined companies for sending to bought lists whose provenance they never checked. If the broker cannot show you when, where and how each record was collected, the risk is priced into the discount. The UK GDPR rules for B2B data are more forgiving than most people think, but only if you can actually evidence them.
Telemarketing data has an extra trap. Calling numbers from a bought list without screening against the Telephone Preference Service is its own PECR breach, separate from anything email-related. Leadistry does not sell phone numbers at all for exactly this reason.
Tell us who you sell to. We find them, with a real email. 25 free leads, no card.
Building your own from the public record
The public record is free and it is the most complete list of UK companies that exists, around five million active ones. You can filter by SIC code, by place, by age, by filing status. For a small patch, an afternoon of Companies House searching genuinely works, and our postcode prospect list recipe shows the exact clicks.
The catch: the public record holds no email addresses and no websites. It never has. So the public record gives you the right companies, and then every contact detail is your own detective work: find the website, find the right person, guess and verify the address, keep notes. Budget a few minutes per company when it goes well. At 300 companies, that is a working week.
Generating a verified list on demand
The third model automates exactly the manual slog above, and nothing else. You describe the companies in plain English or with filters. The software reads the public record, finds each company's own website, extracts the director's name and a real address from it, and verifies that address before charging you. On Leadistry, one credit is one delivered lead: the Companies House record, the director's name, a working website and a verified business email. Rows we cannot complete are never charged and never delivered. Plans start at £29 a month for 900 credits, and the pricing has no per-seat maths.
The honest weaknesses, so you can hold us to our own standard: it is UK-only by design, and there are no phone numbers, on purpose. If your prospecting is international, use a global platform for the international part; our comparison of the software options is open about which tools win which job.
Buy, build or generate: the short version
- Buy when you accept decayed data and legal homework in exchange for having rows today, and your sending domain is expendable. We struggle to recommend it, and not just for the self-interested reason.
- Build when your target list is small and local, your time is genuinely free, and you want to understand the public record first-hand. This is also the best way to learn what good data looks like.
- Generate when you want the public record's completeness with contact details you can defend, priced per delivered row rather than per promise.
Questions people ask
Is it legal to buy email lists in the UK?
Buying is legal. Using what you bought is where the duties bite: under UK GDPR you must hold a lawful basis and be able to say where each record came from, and under PECR the rules differ between limited companies and sole traders, which most brokers never separate for you. Our guide to emailing sole traders under PECR covers that line in detail.
How much does a B2B email list cost in the UK?
Brokers usually price per thousand records, and the price says nothing about deliverability. On the generate model you pay per verified row instead: on Leadistry, £29 covers 900 delivered leads, each with a verified email, which is about 3.2p a lead.
What bounce rate should I expect?
From a verified, freshly generated list, well under 2%. From a bought list, the honest answer is that nobody knows until you send, and by the time you know, your domain reputation has already paid for the experiment.
Can I get a free B2B email list?
The public record itself is free and it is the raw material for every paid list anyway. What costs money is the contact layer. Leadistry's trial gives you 25 delivered leads with no card, which is a real, verified list for nothing, and a fair way to test whether the generate model fits before paying anyone.