How to build a B2B lead list from public data, for free

You know what you sell and roughly who needs it. What you do not have is a list: real businesses, with a reason to talk to you now and a way to reach them. Paid databases promise that list, but they cost money every month, go stale quickly and are full of the same names every other seller is emailing.

There is another way. Governments in most countries publish who has just formed a company, who is buying through public tenders and who is officially trading. Companies publish their own job posts, team pages and contact details. Put together carefully, these free public sources give you a smaller list, but a fresher and far more useful one. This post shows how to build it step by step, wherever you are, and how to keep it clean enough to actually use.

Start with who you want, not where to look

Public data is enormous, and a raw export of any register is mostly businesses you could never serve. Before you open a single source, write down in two or three lines who your best client is: the industry, the size, the place and the moment they are most likely to need you. If you have not done this yet, our ideal customer profile template takes about twenty minutes.

Then turn that description into filters you can apply to a register: an industry or activity code, a region, an age (for example, formed in the last 90 days) and a must-have, such as a working website. These four filters do most of the work for you.

Where free public business data lives

Each country organises its records differently, but the same three kinds of source exist almost everywhere: a company register, a public procurement portal and the businesses' own websites. Here are the main free starting points for some common markets.

Company registers

• United Kingdom: Companies House lets you search the register, and GOV.UK confirms you can get some company details for free, including the registered address, incorporation date and current and resigned directors.
• Australia: ABN Lookup gives free access to public Australian Business Number information, searchable by ABN, ACN or business name.
• Canada: the Corporations Canada search confirms federal corporations by name or number. Provincial companies sit in each province's own registry.
• European Union: every member state runs its own business register, and most offer at least a basic free name search.
• India: the Ministry of Corporate Affairs publishes basic company and LLP master data.
• United States: there is no single national register; each state keeps its own, and some industries have national ones too. Our guide to finding new businesses lists the useful ones.

Public tenders and contracts

Public buyers have to advertise much of what they buy, which makes tenders one of the clearest buying signals there is. In the UK, Find a Tender is where public sector buyers publish procurement notices, and Contracts Finder covers government contracts worth over £12,000 including VAT. In the US, SAM.gov Contract Opportunities lists federal procurement notices, and anyone can search them without an account.

Tenders help twice. You can bid yourself (see how to find government contracts as a small business), or you can treat award notices as leads: a company that just won a large public contract often needs extra hands, software, subcontractors or recruitment help to deliver it.

What companies publish themselves

A company's own website, careers page and press page are public data too. A new job post is one of the best signs a team is growing and spending, as we explain in hiring signals: job posts that point to buyers. Funding announcements and news of a new office or product launch work the same way.

Build the list step by step

1. Open a spreadsheet with these columns: company name, register number, country and region, industry, date formed, website, published email or phone, source of each contact, reason to talk now, status and next step.
2. Pull candidates from one register using your filters: industry, region and a recent formation date. Start with 100 or so, not 10,000.
3. Remove the obvious misfits: dormant companies, holding companies, businesses far outside the region you serve and anything with no trace online.
4. Visit each remaining website. Note what the business does in one line, and whether it looks like your ideal client. This is the step most people skip, and it is where a list becomes useful.
5. Add a reason to talk now from a second source: a recent tender award, a new job post, a funding round or a launch.
6. Record the published contact: the email or phone the business shows on its own site, and the page where you found it.
7. Rank the list: best fit and freshest reason first. Contact the top 20 this week, not all of it at once.

Seven steps sounds like a lot, and by hand it is. Allow a few minutes per business for steps four to six. That is still faster than cleaning up a bought list full of closed companies and bouncing addresses, and you finish with a reason to write to every row.

Which public signal tells you what

One signal makes a business worth a look. Two signals together, say a company formed six months ago that has just posted its first three jobs, usually make it worth a message today. For more on reading these, see our buying signals guide.

Finding the right contact, the honest way

Registers usually give you a company and sometimes its directors' names, but rarely an email address. Resist the urge to fill the gap with guesses. Use only what the business has made public itself: the address on its contact page, a named person's email on its team page, a phone number in its footer. When a company's own published addresses show a clear pattern, a work email in that same format can be a reasonable next step, but label it as likely, not confirmed. Never guess at someone's personal email.

Write down where each contact came from. If someone asks how you got their address, you can answer in one sentence, and you can remove them cleanly if they ask. Our guide on finding a work email the right way covers this in more detail.

• Avoid: bought or rented lists, leaked databases and data copied from sites whose terms forbid it.
• Prefer: the company's own website, official registers and announcements the company made itself.
• Small businesses: a generic address such as hello@ often reaches the owner directly, so do not dismiss it.

Keep it legal and keep it clean

Business email is not a free-for-all, and the rules differ by country. In the United States, the FTC is clear that the CAN-SPAM Act makes no exception for business-to-business email. Commercial messages must include your valid physical postal address and a clear way to opt out, and opt-out requests must be honoured within 10 business days. The UK, the EU, Canada and Australia all have their own rules on electronic marketing, some stricter, so check your national regulator's guidance before you send.

Clean lists also land better. Fewer bounces and fewer complaints protect your mailbox's reputation. Read cold email deliverability for Gmail, Yahoo and Outlook before your first send.

• Send from your own mailbox, a few emails a day at first, never from a fresh domain blasting hundreds.
• Say who you are and why you are writing to this business, in the first two lines.
• Stop following up the moment someone replies, and never email anyone who opts out again.
• Revisit the list monthly: remove closed companies and refresh the reason to talk.

How FarLeads does the same work faster

Everything above works with a spreadsheet and patience. FarLeads does the slow parts for you: it gathers new businesses, companies that are hiring, companies that just raised money and open public contracts from official records and public listings, shows each business once, and uses AI to score how well it fits the ideal client you describe. Its business data covers the United States today, and you can use it from any country, which suits freelancers and agencies anywhere who sell into the US market.

Each contact it shows tells you where it was found and how sure it is, and work emails built from a company's own published format are labelled Likely. When you are ready to write, campaigns send from your own mailbox and stop following up when someone replies.