If you’re sending bulk emails and want your messages to land somewhere other than the spam folder—or worse, bounce into oblivion—email list verification isn’t optional. It’s the first real sanity check before you hit “send.” This guide is for anyone who needs to scrub a big list, whether you’re a marketer, a founder who bought a list (not judging, but tread carefully), or just cleaning house.
I’ll show you, step by step, how to use Truemail to verify your email lists. I’ll also call out the gotchas and what’s not worth stressing over. You don’t need to be technical, but a little patience will help.
Why bother verifying email lists?
Let’s be blunt: Sending to a dirty list is asking for trouble. Here’s what happens if you don’t clean your list: - High bounce rates tank your sender reputation. - More emails get flagged as spam (even to real addresses). - You might get blocked by your email service provider. - You’re paying to send emails that’ll never arrive.
List verification is about removing dead weight—invalid, disposable, or risky emails—so your messages reach real people.
Before you start: What you need
- Your email list in a spreadsheet or CSV format (Excel, Google Sheets, etc.). Truemail supports CSV, which is easiest.
- A Truemail account (free or paid, depending on your list size).
- A web browser. Truemail is cloud-based, so there’s nothing to install.
Pro tip: Clean up your spreadsheet first—remove obvious typos, duplicates, or blank rows. Verification tools are good, but they’re not magic.
Step 1: Sign up and log into Truemail
If you don’t already have a Truemail account, head over and sign up. The free plan lets you test the waters with a small batch, but for big lists, expect to pay. Most services in this space charge per verification, and Truemail is no exception. They’re not the cheapest, but they’re not price-gouging either.
Watch out for:
- Burner email addresses for sign-up—they might block or limit free trials if you use them.
- Forgetting your login. Set up 2FA if you care about security.
Step 2: Prepare your CSV file
This step trips up a lot of people. Truemail wants a clean CSV—no weird formatting, no extra columns you don’t need.
- Column name: Put all your emails in one column titled
email(lowercase, no spaces, no special characters). - No extra data: Strip out names, phone numbers, etc. This is about emails only.
- No formulas or merged cells: Export as pure CSV from Excel or Google Sheets.
Pro tip: Open your CSV in a plain text editor (like Notepad or VS Code) before uploading. If it looks weird there, it’ll probably break the import.
Step 3: Upload your list to Truemail
Inside Truemail, look for “Bulk Email Verification” or an “Upload List” button. The UI isn’t rocket science, but it does make you jump through a couple of hoops:
- Click “New Verification” or similar.
- Select your file and upload it.
- Confirm the column mapping (double-check it’s picking up your email addresses and not something else).
Watch out for:
- File size limits. Massive lists (think 100,000+) might need to be split into smaller chunks.
- Encoding issues. If you get weird errors, try saving your CSV as UTF-8.
Ignore:
- Any upsells for “extra accuracy” or “priority processing.” Basic verification is usually enough unless you’re running a huge campaign.
Step 4: Start the verification process
Once your file is uploaded and mapped, hit the button to start verification. Truemail will chew through your list, checking each address using a mix of syntax checks, domain/MX lookups, and SMTP pinging.
What’s actually happening: - Syntax check: Is the email formatted like an email? (Obvious, but necessary.) - Domain check: Does the domain exist and accept mail? - Mailbox ping: Is the specific mailbox real? (Not every service can do this for all domains, especially Gmail, so don’t expect miracles.)
How long does it take?
- Small lists (under 1,000): A few minutes.
- Medium lists (10,000+): Maybe 10–30 minutes.
- Giant lists: Go make coffee.
Don’t panic if:
- Some emails are marked as “unknown” or “catch-all.” That’s a limitation of email verification in general, not just Truemail.
Step 5: Review your results
Once it’s done, you’ll get a downloadable report. The results are usually split into:
- Valid: These addresses should be safe to send to.
- Invalid: These are dead or malformed—delete them.
- Catch-all: The domain accepts all email, so it’s a gamble. Some real, some fake.
- Unknown: Truemail couldn’t verify (sometimes because of provider limits or greylisting).
- Disposable/role-based: Temporary signups or addresses like “admin@” or “info@”.
Be ruthless:
- Delete invalid and disposable emails without a second thought.
- Catch-all and unknown? Up to you, but know they’re riskier. If you’re sending something important, exclude them. If you’re OK with some bounces, keep them.
Pro tip: Keep the original list. Never overwrite your raw data—just make a new “clean” version.
Step 6: Download and use your cleaned list
You can export the filtered list directly from Truemail. Usually, it’ll give you a CSV with all the verification statuses. Sort or filter for “valid” only.
- Import into your email platform: Mailchimp, SendGrid, whatever you use—just upload the clean list.
- Don’t upload the whole report: Only send to the “valid” emails. The rest are dead weight or trouble.
Ignore:
- Any push to buy more verifications right away. Clean, then send. See how things perform before spending more.
What works, what doesn’t, and what to skip
What works:
- Basic verification: Cuts out 90% of the junk.
- CSV export: Easy to filter and use.
- Quick processing: Unless you’re dealing with six-figure lists.
What doesn’t:
- Perfect accuracy: No tool, Truemail included, can guarantee 100% accuracy. Some bounces will slip through.
- Role-based detection: Sometimes useful, sometimes just noise. Decide if you care about “info@” or “sales@” addresses.
- Catch-all domains: No tool can reliably verify these. Anyone saying otherwise is overselling.
What to skip:
- Bulk “enrichment” or data append services: Focus on verification, not stuffing your list with more questionable data.
- Overpaying for “premium” checks: For most, standard verification is enough.
Common mistakes to avoid
- Uploading the wrong column: Always double-check the import mapping.
- Not removing duplicates: Save credits and avoid annoying people twice.
- Expecting zero bounces: Set realistic expectations—some will always get through.
- Forgetting to re-verify: Lists decay fast. Re-verify every few months if you’re not mailing often.
Keep it simple (and stay skeptical)
Email verification isn’t glamorous, but it saves you headaches. Don’t get lost in extra features or promises of “perfect deliverability”—just use Truemail to clean your list, send to the valid addresses, and keep an eye on your results. If you’re doing this for the first time, start small, learn from what works, and don’t let perfect be the enemy of good. Your future self (and your inbox placement) will thank you.