Kickbox Pricing: The Ladder and the Opt-In Rule

Kickbox puts a complete verification price ladder on one page, headed "Flexible pricing options for organizations of any size", running from 100 addresses free to a million for $2,999 with no subscription and no quote gate. It is one of the more transparent rate cards in the category.

Kickbox's anti-spam policy, on a different host, sets the condition plainly: "all recipients must have opted-in to receive communications from the verifying entity", and "Purchased lists may not be used with the Services, regardless of the source or permission status". For a cold outbound team, those two sentences decide the purchase before the price does.

Both facts come from Kickbox's own pages, fetched on 1 September 2026. Neither condition appears on the comparison pages ranking for this vendor's pricing, and the ladder several of them print is materially higher than the one the vendor currently shows.

The published ladder

Thirteen volume steps sit on Kickbox's pricing page in US dollars. Fetched on 1 September 2026 they are 100 verifications free, 500 for $5, 1,000 for $10, 2,500 for $25, 5,000 for $40, 10,000 for $70, 25,000 for $150, 50,000 for $275, 100,000 for $500, 250,000 for $1,100, 500,000 for $1,800, 750,000 for $2,400 and 1,000,000 for $2,999. Above a million it reads "Need more than 1M verifications? Talk to us for custom pricing or volume discounts", and it flags in-page that "This volume qualifies for enterprise pricing".

13published volume steps, with no quote gate

From a free first step up to one million, then custom pricing above that

3result buckets a credit can return

Deliverable, Risky and Undeliverable, with accept-all domains filed under Risky

1 yearcredit expiry from the date of purchase

Stated in the terms of service, and absent from the pricing page

0accuracy figures on the pricing page

Unusual in this category, and the reason the comparison below is about scope rather than accuracy

The unit rate falls from a cent per address at a thousand to about three tenths of a cent at a million, a factor of roughly three across the ladder. That is a normal shape for this category, and the useful comparison is against the per-thousand rates in the wider verification tool comparison, where the same job is priced from under a dollar per thousand at the top of the volume curve to eight dollars per thousand at the bottom.

Two terms on that page improve the effective rate. Under a heading reading "Unknown Verification Results Are Free" it explains: "If we can't provide a definitive result to you, we'll refund the credit." The credit can then be spent re-verifying the same address later or on a different one. And its homepage opens with "Your first 100 verifications are free!"

One term works the other way, and it is not on the pricing page at all. Its terms of service read: "Email verification credits automatically expire one (1) year from the date of purchase." The same document adds that "Kickbox Services are billed in advance and are non-refundable", with no refunds or credits for partial service or for volume that goes unused. So the volume rate at the bottom of the ladder is a real discount only if the credits are consumed inside twelve months.

The ranking pages disagree with each other, not just with the vendor

Three of the pages ranking for this vendor's price were fetched on 1 September 2026, the same day as the vendor's own page, and they do not agree.

Bouncer's Kickbox pricing page summarises the vendor as one where "The pricing starts at $5 for 500 verifications and goes up to $4,000 for 1,000,000 verifications", and lists a ladder reading 10,000 verifications at $80, 25,000 at $200, "50,000 verifications: $400", 100,000 at $800, 250,000 at $1,500, 500,000 at $2,500 and 1,000,000 at $4,000. SyncGTM's Kickbox review lists 10,000 at $70 to $80, 50,000 at $400, 100,000 at $800 and 1,000,000 at $4,000, with a note against the 50,000 row reading "Monthly subscription at $159/mo includes 50K" and one against the 100,000 row reading "ZeroBounce is cheaper at this tier".

1Lookup's Kickbox comparison, fetched the same day, describes the same vendor as one that "uses a credit-based, pay-as-you-go pricing model" "with lower per-verification rates at higher volumes", and lists 100,000 at $500, 250,000 at $1,100 and 1,000,000 at $2,999.

Set those against Kickbox's own page on 1 September 2026, whose thirteen steps run 10,000 at $70, 25,000 at $150, 50,000 at $275, 100,000 at $500, 250,000 at $1,100, 500,000 at $1,800 and 1,000,000 at $2,999. 1Lookup matches it exactly on all three of the tiers it lists. Bouncer and SyncGTM sit above it at every shared tier, by more than 40 percent at 100,000 and by a third at a million.

The interesting part is not that two pages are stale. It is that a reader comparing three pages that all rank for the same query gets two different answers with nothing on any of them saying when it was read, and the one that agrees with the vendor is published by a competitor.

So the habit is worth more than the arithmetic. Treat a price on any third-party page as undated unless it names the day, and open the vendor's own page in the same sitting. That costs a minute and it is the difference between a budget and a guess.

One figure has no counterpart on the vendor's page at all. SyncGTM's note reads "Monthly subscription at $159/mo includes 50K", and no subscription appears anywhere on Kickbox's own pricing page. That makes it a third-party description of a commercial arrangement rather than a published rate, and it wants confirming with the vendor before it goes in a budget.

The opt-in restriction, in the vendor's own words

An anti-spam policy sits on Kickbox's documentation host, and its scope is unusually explicit.

Kickbox opens it by requiring that "all recipients must have opted-in to receive communications from the verifying entity", explains that an opt-in can occur via a sign-up form on a website, a point-of-sale form or a physical sign-up sheet, and then states that "Purchased lists may not be used with the Services, regardless of the source or permission status".

Kickbox then lists the prohibited uses directly. You may not "verify harvested email addresses from web sites or other sources", "verify purchased lists (whether they are opt-in or not)", verify permutations of email addresses, which it calls directory harvesting, or verify addresses generated via email appending. The terms of service carry the matching clause about addresses obtained from a third party or obtained indirectly without the recipients' knowledge and consent.

The Kickbox policy also spells out enforcement rather than leaving it implied. Where non-opted-in verification is suspected, it undertakes to "review your verifications for patterns common to harvested and other non-opted-in lists" and to review any abuse complaint, and it reserves the right to prohibit use of the services at its sole discretion.

What it costsPublished, unambiguous, no quote gate

• Thirteen volume steps, from a free first step up to one million
• The unit rate falls by roughly three times across the ladder
• Unknown results refunded rather than charged
• First 100 verifications free
• Credits expire one year from purchase, per the terms of service

Who may use itThe clause that decides the purchase

• All recipients must have opted in to hear from the verifying entity
• Purchased lists may not be used, regardless of permission status
• Harvested addresses are named as prohibited
• Permutation-generated addresses are named as prohibited
• Verifications are reviewed for patterns common to non-opted-in lists

For an inbound list, a signup file or a CRM database being cleaned before a migration, none of that restricts anything and the price ladder is the whole decision. For a cold outbound list assembled from a data provider, the restriction is the decision, and it is better established before the credits are bought than after the account is reviewed.

What one credit buys

Three result buckets sit on the Kickbox homepage. It labels the first "Deliverable Safe to send addresses", meaning valid and active mailboxes. The second is Risky, which it fills with disposable or temporary addresses, role-based addresses such as info@ and sales@, and accept-all domains. The third is Undeliverable, meaning invalid or fake addresses and syntax errors.

The accept-all placement is the honest one and it matters more than the rate. An accept-all server answers yes to every address at the domain whether the mailbox exists or not, so no verifier can confirm a mailbox behind one. Kickbox files those addresses as Risky rather than scoring them Deliverable, which is the correct behaviour and also the thing that decides your real cost per usable address on an enterprise B2B list, where accept-all domains are common.

The arithmetic that follows is the one to run. If a fifth of a list sits behind accept-all domains, the price per address you can actually act on is a quarter higher than the ladder suggests, before any of the undeliverable results are subtracted. The same effect is worked through in email list cleaning, where cost per thousand is compared against the cost of a bad send rather than against another vendor's rate card.

Two Kickbox products draw on the same credits, under a homepage banner reading "Fast, Reliable, & Accurate Email Verification": bulk Email List Verification for cleaning a file before a send, and an Email Verification API for catching typos and invalid addresses at the point of capture on forms and signups. The API case is where the opt-in policy fits most naturally, since an address captured on your own form is by definition one the recipient submitted.

How this compares on the axes that matter

Against the alternatives, the interesting comparisons are not on the headline rate.

ZeroBounce does not charge for unknown results either and bundles inbox placement tests and blacklist monitoring into the same subscription, which changes the calculus if you would otherwise buy those separately. MillionVerifier buckets results as Good, Risky or Bad and refunds credits on results it cannot verify with certainty, and prices near the bottom of the category's per-thousand range. Emailable is worth reading for the same reason as this page: what one credit actually buys.

The axis nobody publishes comparably is accuracy, because no two vendors run against a shared test set and they differ on whether unknowns and accept-alls are counted at all. The only test that answers your question is a split of a thousand of your own addresses across two vendors, sent, and compared against cold email bounce rate benchmarks.

Our position on this class of tool

We verify every list before it is sent, because verification is the cheapest deliverability insurance available and a bounce rate is the fastest way to lose a sending domain. We run a cheap pass across the whole list first and reserve the expensive steps for what the cheap pass cannot resolve.

We hold accept-all contacts rather than mailing them, and we do not use pattern-guessing tools to declare an address behind an accept-all server valid. That rule costs us reach on enterprise lists and it is what keeps bounce rates low enough that domains survive.

The provider-terms question is part of that same discipline rather than a separate compliance exercise. A vendor whose published policy says your list type may not be verified with its service is telling you something operationally useful before you spend anything, and the honest response is to buy a tool whose terms match the motion rather than to hope the review never happens.

The short version

A complete thirteen-step ladder runs from 100 verifications free to 1,000,000 for $2,999 on the page fetched 1 September 2026, working out from roughly a cent per address at a thousand to about three tenths of a cent at a million.

Unknown results are refunded and the first 100 are free. "Email verification credits automatically expire one (1) year from the date of purchase" under Kickbox's terms of service, and services are billed in advance and non-refundable, so the volume rate is only a discount if the volume is consumed.

Three ranking pages fetched the same day disagree with each other. Bouncer, which summarises the ladder as running "up to $4,000 for 1,000,000 verifications", and SyncGTM both put 50,000 at $400 and 100,000 at $800, while 1Lookup puts 100,000 at $500 and a million at $2,999 and matches the vendor exactly. Read the vendor's page, and note the date on everything else.

The published anti-spam policy restricts the service to opted-in recipients and names purchased lists, harvested addresses, permutations and appended addresses as prohibited, with verifications reviewed for patterns common to non-opted-in lists. For a cold outbound list that clause, not the rate card, is the decision.

If the underlying question is how to build a list worth verifying in the first place, see what a first campaign produces.

Rates, result buckets, terms and policy language verified against Kickbox's own pricing page, homepage, terms of service and anti-spam policy, fetched on 1 September 2026, with dated snapshots retained. The third-party figures are attributed to the named pages on Bouncer, SyncGTM and 1Lookup, each fetched on the same day and retained as a dated snapshot. Figures are US dollars, and the per-verification rates are derived from the package totals on that page. A promotional discount code was displayed on the pricing page at the time of reading and is not reflected in the figures above. Verify current terms with the vendor before relying on them.