Email Verification API Pricing: Cost at 10K, 100K, 1M Calls

Email verification API pricing looks simple: one credit per check. The bill you get at the end of the month is not. Minimum purchases, unknown results, shared credit pools and rate limits all change what each API call really costs. So we priced the same three workloads on six providers: 10,000, 100,000 and 1,000,000 verifications.

Every price below comes from each vendor's public pricing page, checked on 10 November 2026. Prices change often, so confirm on the vendor's page before you buy.

TL;DR#

• At 10,000 checks, Bouncer and Emailable cost $60. ZeroBounce costs $129 on pay-as-you-go.
• At 1,000,000 checks, Bouncer is $2,000, Emailable is $2,100 and ZeroBounce is $3,199. MillionVerifier advertises a 1M pack for $449.
• Unknown results are free at ZeroBounce, Emailable and Bouncer. Tomba's API also skips the charge for unknown and disposable results.
• Subscriptions win when your volume is steady. Pay-as-you-go wins when it is spiky.
• Check what else the credits buy. Some plans share one pool between finding and verifying. Others, like Tomba, give each its own allowance.

How email verification API pricing works#

Almost every provider sells credits. One credit usually equals one verification, whether you call the real-time API or upload a CSV. Emailable states this plainly: bulk, single checks and the API all cost 1 credit per verification.

The differences hide in four places:

1. Billing model. Pay-as-you-go packs are one-time purchases. Subscriptions give a monthly allowance at a lower rate.
2. What is billable. Some providers refund unknown results and duplicates. Others charge for every call.
3. Minimums. ZeroBounce's pay-as-you-go minimum is 2,000 credits for $39. Bouncer's is 1,000 credits for $8.
4. Expiry and rollover. Bouncer, Emailable and MillionVerifier say their credits never expire. ZeroBounce says expiry rules may apply to pay-as-you-go credits without a subscription.

For an API, a fifth factor matters too: rate limits. A cheap plan that caps requests per second can slow down a signup form or a nightly sync. That is a cost even if it never shows up on the invoice.

Email verification API pricing at 10K, 100K and 1M calls#

Here is what a one-time, pay-as-you-go purchase costs at each volume. These are the list prices shown on each pricing page.

Turned into a price per 1,000 checks, the spread is clear:

Two things stand out. First, volume discounts are steep. Bouncer's price per check falls by two thirds between 10,000 and 1,000,000. Second, the gap between providers shrinks at scale, except for MillionVerifier, which prices for very large lists.

We could not load NeverBounce's or Kickbox's pricing pages for this review, so they are not in the tables.

Subscription plans: cheaper per check, if you use them#

Subscriptions change email verification API pricing the most when your volume is steady. If your app verifies about the same number of addresses every month, a plan usually costs less per check.

• Emailable takes 15% off on a monthly plan. 10,000 credits drop from $60 to $51 a month, and 100,000 from $420 to $357. Unused credits roll over.
• ZeroBounce ONE costs $99 a month with a minimum of 10,000 credits. Annual billing takes 20% off, and unused credits roll over.
• Hunter bundles verification into its finder plans. Starter is $49 a month for 2,000 credits, Growth $149 for 10,000 and Scale $299 for 25,000. A verification costs 0.5 credit, but the same pool also pays for searches.
• Tomba plans give separate monthly allowances for searches and verifications. Basic is $49 a month with 2,500 verification credits. Growth is $89 for 5,000, Pro $199 for 20,000 and Pro Plus $449 for 50,000. Each plan also includes a search allowance of the same size, which verification never draws from. Yearly billing takes 25% off. See Tomba pricing for every tier.

Shared pools need care. On a plan where finding and verifying draw from one balance, a busy prospecting week can leave nothing for your API. Separate allowances make the monthly verification budget predictable.

What makes an API call billable?#

This is the part of email verification API pricing that list prices hide. Two providers with the same price per credit can send very different bills. Read the billing rules, not just the price.

Unknown results. Catch-all servers, greylisting and timeouts all produce "unknown". ZeroBounce says it never charges for them. Emailable returns those credits to your balance when a list finishes. Bouncer does not charge for them either. On the Tomba API, the Email Verifier endpoint costs 1 verification credit only when the status is not disposable or unknown.

Errors and retries. Your code will retry. If a 429 or a server error costs a credit, retries add up fast. Tomba does not charge for errors, 429 and 451 responses, or repeat calls within your usage window.

Duplicates. Bouncer, Emailable and ZeroBounce don't charge for duplicate addresses in an uploaded list. For single API calls, dedupe on your side before you call.

Catch-all checks. Some providers bill deeper checks separately. DeBounce, for example, lists catch-all validation at 10 credits per check. If many of your contacts sit on accept-all domains, a dedicated catch-all verifier may be the bigger line item.

Rate limits: the cost that isn't on the invoice#

Rate limits never appear in email verification API pricing tables, but they still cost you. A real-time API sits in your signup flow or your CRM sync. If it throttles, users wait or jobs back up. Before you pick a plan, check three things:

1. Requests per second and per minute. These matter most for signup forms and webhooks.
2. Requests per day. These matter most for nightly batch syncs.
3. Whether limits apply per key or per account. Several keys rarely add capacity.

On Tomba, every API key on an account shares the same counters. Pro Plus and Scale have no per-second, per-minute or daily limits on the main endpoints, and Enterprise has no per-second or per-minute limit. The rate limits docs list the numbers for every plan. For very large lists, bulk endpoints are often the better fit. Our guide to the bulk email verification API covers when to switch.

Which pricing model fits your workload?#

The best email verification API pricing for you depends on how your traffic behaves, not on the lowest headline rate.

Three examples make it concrete:

• A SaaS app checking 8,000 signups a month. A 10,000-credit pack from Bouncer or Emailable costs $60 and lasts longer than a month, since their credits never expire.
• A RevOps team checking 100,000 CRM records a month. Emailable's monthly plan is $357 for 100,000 credits, against $420 one-time. That saves $756 a year.
• A data provider checking 1,000,000 addresses a month. Bouncer's list price is $2,000 and Emailable's is $2,100. At this volume, ask sales for a quote; both pages point large buyers there.

How to cut your verification API bill#

Small habits lower what you really pay more than a switch of vendor does.

1. Validate syntax locally first. A regex and an MX lookup catch typos for free. Spend credits only on addresses that pass.
2. Cache recent results. If you verified an address last week, you rarely need to pay again today.
3. Dedupe before every call. Duplicates in a CRM sync are pure waste.
4. Prefer providers that don't bill unknowns. On lists heavy with catch-all domains, this alone can change the ranking.
5. Re-check your tier every quarter. Volume grows. A plan that fit in January may cost too much by June.

For a wider look at list-cleaning prices beyond APIs, see our cheapest email verification service comparison.

FAQ#

How much does an email verification API cost per call?#

At list price, from about $0.0005 per call (MillionVerifier's advertised 1M pack) to about $0.02 (ZeroBounce's 2,000-credit minimum). Small packs cost the most per check. Million-check packs cost the least.

Do email verification APIs charge for unknown results?#

ZeroBounce, Emailable and Bouncer say they don't. Tomba's Email Verifier endpoint charges a credit only when the status is not disposable or unknown. Always check the billing page, since policies differ.

Is pay-as-you-go or a subscription cheaper?#

A subscription is cheaper per check if you use most of your allowance each month. Pay-as-you-go is cheaper if your volume is uneven, as long as the credits don't expire.

Is real-time API verification priced differently from bulk?#

Usually not. In email verification API pricing, Emailable and ZeroBounce charge one credit per verification for both. The difference is in rate limits and speed, not in the price per check.

The bottom line#

Email verification API pricing in 2026 is cheapest per check at high volume and on plans that don't bill unknown results. Bouncer and Emailable lead on list price for 10,000 to 1,000,000 checks. Subscriptions save 15–20% when your traffic is steady.

If you also need to find the addresses you verify, a separate verification allowance keeps both budgets predictable. Tomba Email Finder finds professional emails by domain, name or company, and every paid plan adds a verification allowance of the same size for the email verifier and the API. Create a free account to try the finder, then pick a plan when you are ready to verify at volume.