# Spaw vs NeverBounce: email verification API comparison

How Spaw and NeverBounce compare on pricing, billing rules, verification depth and limits, from NeverBounce's public pages checked on 2026-09-03. Corrections: support@spaw.co.

| | Spaw | NeverBounce |
| --- | --- | --- |
| Pricing model | Pay-as-you-go credit packs bought through Stripe Checkout; no subscription, credits never expire | not published |
| Free tier | 10 free credits every month, no card required | not published |
| Price per 1,000 at about 10k | $7.80 (Growth pack: 5,000 credits for $39) | not published |
| Price per 1,000 at about 100k | $4.99 (Volume pack: 100,000 credits for $499) | not published |
| Unknown or catch-all results billed | Yes, by verdict: a deliverable or risky answer costs 1 credit even when the mailbox is unconfirmed; the automatic re-checks are free | not published |
| Undeliverable results billed | No, undeliverable verdicts are always free | not published |
| SMTP mailbox check | Yes | not published |
| Catch-all handling | A catch-all answer is remembered per domain for 7 days, and every unconfirmed mailbox carries a published 0 to 100 mailbox_confidence estimate | catchall is one of the result codes alongside valid, invalid, disposable and unknown; jobs with a high rate of unknowns can be sent for a manual review |
| Bulk limit | 100,000 addresses per bulk job, with an HMAC-signed completion webhook | Lists of millions should be split into jobs of 1,000,000 addresses; 10 concurrent jobs and at most 50 runs a day per account, and no more than 10 jobs per 100,000 items an hour |
| Batch API | 50 addresses per synchronous request, probes sent concurrently | Bulk jobs through the jobs API (create, status, download) |
| Rate limit | 5 requests per second per key | Job creation limits as above; per-request limits for the single-check endpoint are not published on the pages checked |
| Official SDKs | Python, Node.js, PHP | PHP, Node.js, Python, Ruby, Go, .NET |
| Data retention | Lookup history kept for 30 days, then pruned; test addresses are never logged | not published |

## When NeverBounce fits better

Teams that clean large lists through jobs and want official wrappers in six languages plus an n8n node.

- Official n8n node
- Manual review process for jobs with many unknown results
- Owned by ZoomInfo

## When Spaw fits better

Developers who want one flat price per answered lookup, a transparent risk score, and an API that documents every field.

- NeverBounce's pricing pages blocked automated reading when we checked, so its rates are not reproduced here; Spaw's packs and free grant are listed at spaw.co/pricing
- Spaw runs the SMTP handshake on every lookup and bills nothing for undeliverable verdicts
- Spaw's bulk jobs take 100,000 addresses with a signed completion webhook; NeverBounce asks for 1,000,000-address chunks, 10 concurrent jobs and 50 runs a day
- Spaw returns 27 named fields and a machine-readable reason per address

## Questions

**Does Spaw charge for catch-all or unknown results?** Spaw bills per answer, not per probe outcome: a lookup that comes back deliverable or risky costs 1 credit even when the mailbox could not be confirmed, for example on a catch-all domain or after greylisting. Undeliverable verdicts, invalid input, repeats within 7 days and the automatic re-checks behind callback_url are free. NeverBounce does not publish how it bills them.

**Can I move a list from NeverBounce to Spaw?** Yes. Upload the CSV to the dashboard or POST it to the bulk endpoint; Spaw keeps your columns, adds the verdict columns, and lets you download only the deliverable, risky or undeliverable rows. Addresses that come back undeliverable join your suppression list so later runs skip them for free.

**Is there a free tier?** Every Spaw account receives 10 free credits at the start of each month with no card on file, and unused credits accumulate. NeverBounce does not publish a free tier on the pages checked.

## Sources (checked 2026-09-03)

- [NeverBounce usage guidelines](https://developers.neverbounce.com/reference/usage-guidelines)
- [NeverBounce verifying a list](https://developers.neverbounce.com/docs/verifying-a-list)
- [NeverBounce GitHub organization](https://github.com/NeverBounce)

NeverBounce is a trademark of its owner. Spaw is not affiliated with it.

Reference: https://spaw.co/compare/neverbounce