Buyer guide · SimpleVerifier Team
How to verify an email list before a cold email campaign
Run the list through a verifier that does an SMTP mailbox check before you import it into your sending tool. Send to valid addresses, remove invalid ones, and hold back or send slowly to risky ones: catch-all domains and servers that would not confirm the mailbox. Re-check any list older than a few weeks. The first 100 checks are free.
Bounces on a cold domain do more damage than on a warm one: a new sending domain has no history to absorb them, and mailbox providers and sending tools both watch the bounce rate. A list bought, scraped or exported from a lead database months ago will contain mailboxes that have since closed, and a verifier is the only way to find them without sending.
The cold email list checker previews 10 addresses free with no account and carries the list to the full check. Exports from Apollo have their own import guide, and the Instantly and Smartlead pages cover getting the cleaned file back in.
What one pre-campaign check costs, by vendor
| Vendor | 2,500 once | 10,000 once | 50,000 once |
|---|---|---|---|
| SimpleVerifier | $9 | $19 | $29.99 |
| EmailValidation.io | $9.99 | $19.98 | $69.98 |
| Reoon | $11.90 | $11.90 | $58.95 |
| Bouncify | $12 | $19 | $78 |
| DeBounce | $13.80 | $23 | $69 |
| Email List Validation | $14 | $49 | $158 |
| Mailboxlayer | $14.99 | $29.98 | $74.99 |
| EmailListVerify | $16 | $25 | $89 |
| Abstract API | $19 | $38 | $99 |
| Pabbly Email Verification | $19 | $29 | Not published |
| Bouncer | $19.20 | $48 | $200 |
| NeverBounce | $20 | $49 | Not published |
| QuickEmailVerification | $20 | $60 | $200 |
| Clearout | $23 | $58 | $290 |
| Email Hippo | $24.70 | $88.40 | $312 |
| Kickbox | $25 | $70 | $275 |
| MailerCheck | $25 | $80 | $300 |
| Xverify | $25 | $70 | $250 |
| Mailfloss | $29 | $29 | $118 |
| MailboxValidator | $29.95 | $59.95 | $139.95 |
| Emailable | $32.30 | $51 | $208.25 |
| MillionVerifier | $39 | $39 | $89 |
| Enrichley | $59 | $118 | $298 |
| ZeroBounce | $69 | $99 | $379 |
Each vendor's lowest published route for one list of that size, read from its own pricing page. Ours is one month of the smallest plan that covers it. Where a vendor is below our figure, it costs less for that job. Each vendor links to its comparison page, which records the date its prices were read. Check their site for current pricing before you buy.
Test it on a real address first
Type any address. It gets the same check the paid plans run: syntax, the domain’s mail servers and, where the provider allows it, a live mailbox check. Nothing is sent to the address.
Five checks a minute, no account needed. Nothing is sent to the address — we ask its mail server whether the mailbox exists, then disconnect.
Have a list? Sign in with Google and the first 100 addresses are checked free, with results to download. No card.
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The order that works
1. Remove duplicates and your do-not-contact list first, so you do not pay to check addresses you will never send to. 2. Verify the rest. 3. Import the valid rows into the sending tool. 4. Decide on risky rows separately: a small, slow test send on a warmed inbox, or leave them out. 5. Keep invalid rows on a suppression list so they never come back in the next export.
On SimpleVerifier, each result carries a send advice column (safe to send, send with care, retry later) and a reason, and the results page can download only the safe-to-send rows.
What a verifier cannot tell you
A catch-all domain accepts every address during the check, so a verifier cannot say whether a particular person's mailbox exists there; those rows come back risky, not valid. Yahoo and AOL behave the same way. SimpleVerifier does not probe Microsoft consumer mailboxes (Outlook.com, Hotmail, Live) or iCloud, so those are risky too. A valid result means the mailbox exists today; it says nothing about whether the person will reply or whether the message lands in the inbox.
How long it takes
Mailbox checks are paced, because mail servers slow down or block verifiers that probe too fast, and the daily check capacity is shared between customers. Addresses that need no mailbox check, such as broken syntax, dead domains and disposable addresses, come back at once. The rest run in a queue, and the job card shows an estimated finish time. Start the check the day before the campaign rather than the hour before.
Common questions
- Should I send cold email to risky or catch-all addresses?
- Not in the main campaign. A verifier cannot confirm them, so some will bounce. Either leave them out or send a small, slow batch from a warmed inbox and stop if the bounces climb.
- How often should I re-verify a cold email list?
- Before every campaign that uses a list more than a few weeks old. People change jobs and companies close mailboxes, so a list that was clean last quarter is not clean now. Results confirmed in the last 14 days are reused at no cost on SimpleVerifier.
- Can I verify leads that are already in Instantly or Smartlead?
- Yes. Instantly has its own verifier for leads in a campaign, and SimpleVerifier's Instantly and Smartlead integrations read a campaign through the tool's API and, if you choose, delete the invalid leads from it. Verifying before import works with any sending tool and keeps the invalid rows on your own suppression list.
- How much does it cost to verify a cold email list?
- On SimpleVerifier the first 100 checks are free; after that Starter is $9 a month for 2,500 emails a month, Growth $19 for 10,000 emails a month, and Pro $29.99. Other vendors' prices for the same list are in the table above.
Check your list before you send
Pro is $29.99 a month and never cuts you off: the first 100,000 emails a month run at full speed, then big lists run slower. CSV uploads, the API (10,000 calls a month, then $1.50 per 1,000), the Google Sheets add-on and the email finder are included, and you can cancel any time. For smaller volumes, Starter is $9 a month for 2,500 emails a month and Growth $19 a month for 10,000 emails a month.
The first 100 email checks are free with a Google sign-in, no card, on the same engine the paid plans use.