Almost every company you would sell to has email addresses. The hard part is getting the right address, from a source you can name. Any list of companies with email addresses holds two kinds of address. One is a generic inbox, such as info@ or sales@. The other is a named person's work address.
Lists like this come from eight main sources, from free PDF uploads to B2B data platforms. Only named decision-makers, pulled from a filtered platform and verified before the first message goes out, are worth sending to.
What does a list of companies with email addresses actually contain?
The generic-versus-named split changes both the legal rules and the odds of reaching a buyer.
On the legal side, the UK regulator treats an address like initials.lastname@company.com as personal data under UK GDPR, and treats info@company.com as outside it (ICO B2B marketing guidance).
Commercially, info@ is read by whoever sorts the mail. Your offer may never reach the person who signs. Some of that mail never even lands. ZeroBounce notes that some providers may bounce email sent to role-based addresses like info@, and it advises against using them for mass B2B email.
When a campaign fails, check the list before you touch the copy. Wording cannot make up for a poor list or a sender with a bad reputation.
Where do company email lists come from, and what is each source worth?
Read it top down: the higher the row, the closer you get to a named buyer whose address you can account for.
| Source | What you get | Named people? | Cost | Legal exposure | Verdict |
|---|---|---|---|---|---|
| B2B data platforms (Sales Navigator, Apollo, UpLead, ZoomInfo, RocketReach) | People filtered by title, industry, size and country | Yes | Subscription; prices in what B2B contact data costs | Standard B2B rules, and you know the source | Start here |
| Email finder tools | An address for a name and domain you already have | Yes | Credits per email | Same as platforms | Fill gaps |
| Company websites | Contact pages, sometimes team pages | Rarely | Free but slow | Low for info@, GDPR duties for named staff | Small or local lists |
| Public registers (Companies House) | Company names and basic register data | No | Free | Low, it holds no personal contact data | Size the market |
| Online directories | Listings with generic inboxes | Rarely | Free to low | Low | Company discovery only |
| List brokers | A ready file of contacts | Usually | Per file; no credible published price range | High: unknown origin, against Gmail and Yahoo sender rules | Avoid |
| Freelancer-bought lists | A cheap spreadsheet | Yes | Cheap; no credible published price | High: no source you can name | Avoid |
| Free PDF uploads | Scraped names, phones, some addresses | Sometimes | Free | High: no date, no source | Unusable |
I put platforms first because of my own campaigns: for a UK social media marketing agency, my team pulled lists from Sales Navigator, Apollo and UpLead across 3 niches and booked 714 sales calls in 12 months.
A list built inside those tools beats a scraped one.
I put freelancer lists near the bottom because cheap ones open poorly and bounce hard. Spamhaus groups purchased, rented and scraped lists together. It says they lead to high bounce rates, spam complaints, spamtrap hits and ISP blocks.
ZeroBounce's verification data found 20.19% of the emails it checked were invalid. That figure covers the emails it checks in general, not only bought lists.
Companies House is the best free company source in the UK. It offers a monthly CSV snapshot with basic register data for every live UK company. It is free, unsupported and refreshed within 5 working days of each month end (Companies House). It lists companies, not people: use it to size a UK market, then find the buyers' contact details elsewhere.
Brokers fail on deliverability before the law comes up. Google tells senders: "Don't purchase email addresses from other companies" (Google sender guidelines), and Yahoo says the same about mailing lists (Yahoo Sender Hub). If you are still tempted, read if buying a B2B email list ever makes sense.
Free PDF uploads that rank on Google carry no collection date and no verification record, so you cannot tell anyone where their data came from.
What does a finder tool cost per address?
Hunter publishes clear credit rules, so it makes a clean worked example (no endorsement). At the time of writing, Hunter's pricing page lists 1 credit per email found, 0.5 credit per email verified, 50 free credits a month, and Starter at EUR 49 a month for 2,000 credits.
Say you need 2,000 named addresses, found and verified:
- Finding: 2,000 credits
- Verifying: 1,000 credits
- Total: 3,000 credits, more than Starter's 2,000
At 1.5 credits per address, Starter covers about 1,333 addresses a month, under EUR 0.04 each, and the free plan about 33.
Is it legal to email a company you found online?
The rules differ by market. This is not legal advice.
UK. PECR, the UK's Privacy and Electronic Communications Regulations, puts limited companies, LLPs and Scottish partnerships in a separate group: you can email them without consent. You still have to say who you are, and every message needs an address where the business can unsubscribe (ICO).
A sole trader, like some partnerships, is an individual subscriber under PECR and needs consent (ICO PECR guide).
Named addresses add UK GDPR duties. Finding someone's details in public is not agreement to marketing (ICO), and privacy information for data from another source is due within one month (ICO right to be informed). The ICO marks its B2B marketing guidance as under review after the Data (Use and Access) Act changed parts of the rules.
US. CAN-SPAM has no carve-out for B2B email. Every message must include a working opt-out and a street or postal address, and requests must be honored within 10 business days. Each violating email can cost up to $53,088, and harvesting addresses carries criminal penalties.
EU. If you collected the details from a third party instead of the individual, GDPR Article 14 obliges you to state where they originated, no later than your first message (GDPR). Germany, Austria and the Czech Republic add prior consent rules on top. For those markets my team reaches out on LinkedIn and sends no cold email without a compliant basis.
Canada. CASL allows implied consent for an address the person conspicuously published, with no statement refusing messages. That consent only holds if your message relates to their business role (CASL section 10(9)(b)).
How long does an exported list stay usable?
A list starts aging the day it is exported.
People change jobs. The BLS tenure release for January 2026 is a good marker. Its number: 20.6% of US wage and salary workers had been with their current employer a year or less. So pull a fresh export from live filters for each campaign. My team builds a first list of at least 20,000 contacts. The evidence on how quickly contacts go stale is in how fast B2B data decays.
How my team builds a list instead of buying one
I would not buy a ready-made file for a client. Not once. My team builds each list from filters we set for that client, in the same order:
- Start from the client's past and current customers, then find companies like them.
- Look at past deals and write down who actually signed, such as a CTO or Head of IT for an IT services buyer.
- Exclude generic titles such as Assistant, Manager and Associate.
- Pull the matching people from a filtered platform, using those titles as filters.
- Verify every address through NeverBounce or DeBounce, and keep bounces below 0.5%.
For a US business consulting and coaching firm, my team built the lists in Sales Navigator and ran LinkedIn outbound next to an optimized founder profile and content: 38 of 98 connection requests were accepted, and 204 sales calls were booked in 4 months.
The cheapest list costs the most, because you pay for it later in bounces and a burned sending domain.
On who pays: at my cold email agency, list building sits inside the monthly fee, and the client pays the data tools directly, because the stack changes with industry, market, volume and team size. The full method is in building a lead list worth sending to.
Deciding where your next company list should come from? Book a call and tell me the titles you sell to. I will say which source I would pull them from first.
Questions founders ask about company email lists
Who carries the legal risk if a freelancer or agency built the list?
You still carry it. The FTC says you cannot contract away your CAN-SPAM responsibility, and both the promoted company and the sender can be liable. In Canada, the CRTC says that if you use a third-party list, you must still prove implied consent yourself. Ask every list builder where each address came from.
Do unsubscribes carry over to the next list I build?
They should. Keep a "do not email" list and screen each new list against it, as the ICO recommends. Under GDPR Article 21(3), once someone objects to direct marketing, their data cannot be used for it again. CAN-SPAM also forbids selling or transferring addresses of people who opted out.
How many spam complaints can a company list survive?
Very few. Google wants the spam rate in Postmaster Tools kept under 0.10%, and it must never reach 0.30%. Yahoo sets its limit at 0.30%. A poorly targeted list can cross those lines, and a flagged domain then hurts every later campaign you send from it.
Can I email info@ and other generic company addresses?
In the UK it is the lightest case legally: the ICO treats an address like info@company.com as outside UK GDPR, and a limited company needs no consent as long as you identify yourself and offer an opt-out. Commercially it is the weakest address you can collect.
The mail is read by whoever sorts it, and ZeroBounce advises against role-based addresses for mass B2B email. Use them for small local lists, not for reaching a buyer.