How to Clean a Cognism Export Before Cold Emailing It
Download the revealed contacts from your Cognism list as CSV, keep verified emails, mark unverified ones as risky, set aside invalid, role and off-domain addresses, then check the cleaned file live on the day you load it into the sequencer. A Cognism verification is a good start, not a guarantee for the day you send.
The Cognism export to email list tool does the sorting in your browser. Here's what it does and why.
Step 1: Reveal and download
- In Cognism, open Lists and open the list.
- Reveal the contacts you want. Cognism's pricing page (read 3 November 2026) says one credit is used per revealed contact, viewing contacts you already revealed is free, and credits are reused only when a contact changes jobs.
- Select the revealed contacts and click Download CSV.
Cognism's own help centre wasn't readable to our fetcher when this was written, so these steps come from the tool's researched copy. If your screen differs, the Lists article in Cognism's help centre is the reference.
Step 2: Sort by email quality
Upload the CSV to the Cognism export tool, or sort it yourself:
| Row | What to do | Why |
|---|---|---|
| Verified | Keep | Checked by Cognism; re-check if the download is old |
| Unverified | Keep, mark risky | Not checked at all |
| Invalid | Set aside | Will bounce |
Role address (info@, sales@) |
Set aside | Shared inbox, low reply rate, more complaints |
| Personal webmail | Flag | A personal address on a B2B list needs a reason to be there |
Our post on personal emails in a B2B lead list covers when a Gmail address on a business list is fine and when it isn't.
Step 3: Look at off-domain addresses
When the email's domain doesn't match the company website in the same row, there's usually a reason: a parent company, a regional domain, an old domain after a rebrand, or an address built from a naming pattern rather than found. The tool flags those rows. Check them first; they're over-represented in bounces.
Step 4: Limit contacts per company
Cognism lists are often built by title, so one company can contribute several people with similar roles. Sending to all of them on day one looks automated to the company's mail gateway and to the people, who compare notes. The contacts per company limiter keeps the first two or three and holds the rest for later. The job title seniority filter helps decide which ones to keep.
Step 5: Check the cleaned file live
B2B data decays as people move jobs and companies change mail providers, and a list downloaded today may have been verified weeks ago. Upload the cleaned file at /verify: every address gets a live mailbox check, and valid, risky and invalid download as separate files. Catch-all domains are marked, which matters for UK and European corporate domains behind security gateways.
Then load only the valid file into the main campaign, and put catch-all addresses in a smaller, slower one or drop them. Our guides to catch-all leads in sequences and re-verifying leads older than 30 days cover both.
UK and EU rules
Cognism is widely used for European outreach, so the rules there matter. In the UK, PECR generally allows marketing email to corporate subscribers without prior consent, as long as you identify yourself and offer an opt-out, but sole traders and some partnerships count as individuals and need consent. UK GDPR still applies to the personal data itself. Our posts on GDPR and B2B cold email and whether collecting business emails is legal go further. Verification removes addresses that will bounce; it doesn't change who you're allowed to email.
Honest limits
- Column names aren't published. Cognism doesn't document its CSV headings; the tool finds the email and email quality columns by name, so check the notes above the result.
- Phones aren't carried through. The output is an email list.
- Catch-all domains stay unproven. No mailbox check can confirm an address on a server that accepts everything.
If your Cognism data has been bouncing more than it used to, our post on lead data quality dropping before renewal shows how to measure it before the renewal call.
Where SimpleVerifier fits
The export tool is free and runs in your browser. The live check is the paid part: the first 100 checks are free with a Google sign-in on the verify page. Pro is $39 a month with the first 100,000 checks a month at full speed, then slower, never cut off, and one-time packs of 10,000 checks for $15 never expire. See pricing.
Common questions
Does Cognism verify emails?
Cognism labels email quality in its data, and its exports carry that label. It's a point-in-time result. People change jobs and companies change mail providers, so a live check on send day catches addresses that have closed since.
Do I lose credits by downloading a Cognism list?
Downloading itself isn't the cost; revealing is. Cognism's pricing page says one credit is used per revealed contact and viewing previously revealed contacts costs nothing. Only revealed contacts can be downloaded.
Can I clean a Cognism export that's already in Salesforce or HubSpot?
Yes. Export the contacts from the CRM; the email and company columns are found by name even when the CRM renamed the Cognism fields.
Is it legal to cold email a Cognism list in the UK?
B2B email to corporate subscribers in the UK is generally allowed under PECR with an opt-out in every message, while UK GDPR still applies to personal data. Sole traders and some partnerships are treated as individuals and need consent. Check with your own adviser; the cleaning steps don't change the rules.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.