Some links on this page are affiliate links. If you buy through them, BestStacked may earn a commission at no extra cost to you. It never affects our scores, rankings or verdicts. Full disclosure.
ZeroBounce Review
Reviewed by Carlos Gil · Founder & Editor, The Best Network
Updated 8 min readEditorially reviewed
Quick facts
- Starting price
- Free 100 credits/mo; pay-as-you-go from $39 for 2,000 credits; ONE from $99/mo ($79/mo billed annually)
- Free plan
- Yes
- Best for
- Marketers, sales teams and agencies who clean lists before campaigns or validate sign-ups in real time and want deliverability monitoring from the same vendor
- Platforms
- Web app, REST API with SDKs, iOS app, browser extensions
BestStacked Score
Weighted average of 5 categories. Methodology below.
Quick answer
Is ZeroBounce worth it?
ZeroBounce is an email verification service: upload a list or call its API and it flags addresses that are invalid, risky, disposable, catch-all or likely spam traps, so fewer of your emails bounce. On October 18, 2026, pay-as-you-go credits started at $39 for 2,000 checks and fell to $649 for 100,000. The ZeroBounce ONE subscription started at $99 a month, or $79 a month billed annually, for 10,000 credits plus warmup, inbox placement tests and blacklist and DMARC monitoring. A free account gets 100 credits a month with a business email domain. ZeroBounce advertises 99.6% accuracy; BestStacked hasn't verified that figure, and verification lowers bounce risk without guaranteeing inbox placement.
- Best for
- Teams that clean lists regularly, or validate sign-ups in real time, and also want deliverability monitoring in one account.
- Skip it if
- You only need cheap one-off list cleaning: NeverBounce and Kickbox listed lower per-credit prices on the same day.
- Strongest capability
- Verification, AI scoring, Email Finder, warmup, inbox placement tests and blacklist and DMARC monitoring share one credit balance and one dashboard.
- Biggest limitation
- Credit purchases are non-refundable, and the ONE money-back guarantee ends once you validate more than 500 emails.
- Current cost
- Free 100 credits/mo; 2,000 credits $39, 10,000 $129, 100,000 $649; ONE $99/mo or $79/mo billed annually for 10,000 credits a month.
The Verdict
ZeroBounce does the core job of an email verifier and then goes further than most rivals: the same account covers AI scoring of catch-all addresses, an Email Finder, Activity Data, domain warmup, inbox placement tests, server tests, blacklist monitoring and DMARC reports. Its integrations directory lists 95 connections, including HubSpot, Mailchimp, Klaviyo, Salesforce, Zapier, Make and an MCP server, and its security page lists SOC 2 Type 2, ISO 27001 and HIPAA (with a BAA). Support is advertised as 24/7 by chat, email and phone. The catch is cost and fine print: per-credit prices are higher than NeverBounce's or Kickbox's, credit purchases are non-refundable, the ONE refund only applies before you've validated 500 emails, and the pricing page says credits never expire while the terms say credits bought by newer accounts expire after two years without an active subscription. The 99.6% accuracy figure is ZeroBounce's own claim. We score ZeroBounce 8.3/10, provisionally.
Best for
Teams that verify lists every month or in real time and want warmup, inbox tests and blacklist and DMARC monitoring from the same vendor.
Skip if
You clean a list once or twice a year and only need the lowest price per check, or you need a refund after trying the service on a real list.
AlternativesNeverBounce, Kickbox, Hunter
The Background
What Is ZeroBounce?
ZeroBounce is an email verification and deliverability platform run by Hertza L.L.C., which trades as ZeroBounce from Santa Barbara, California. Its core service checks whether an email address exists and is safe to send to: you upload a file, connect a tool, or call the API at sign-up time, and each address comes back with a status such as valid, invalid, catch-all, spam trap, abuse, do-not-mail or unknown. Around that core it sells AI scoring (a 1 to 10 rating of how likely an address reaches a real person, aimed at catch-all and uncertain addresses), Activity Data (which addresses showed email activity in the past 30 to 180 days), an Email Finder that guesses and validates business addresses from a name and domain, and a set of deliverability tools: warmup, inbox placement tests, email server tests, blacklist monitoring, DMARC monitoring and a deliverability dashboard. Everything runs on credits. What verification doesn't do matters as much: it removes addresses likely to bounce, but it can't make mailbox providers put your email in the inbox. Sender reputation, authentication, content and how people engage with your mail still decide that. Verification also doesn't make a purchased or scraped list lawful to email under CAN-SPAM, GDPR or similar rules.
The Product
ZeroBounce Features: What You Actually Get
Bulk and real-time email validation
Upload a list (100 addresses minimum for the bulk uploader on the homepage) or call the validation API from a sign-up form. ZeroBounce returns detailed status codes, flags catch-all domains, disposable and role-based addresses, and says it detects spam traps and abuse accounts. Unknown results and duplicate addresses cost no credits. Its FAQ says it cleans 100,000 addresses in 45 minutes and its pages advertise 99.6% accuracy as guaranteed; we didn't find published terms explaining how that guarantee is measured or what remedy applies, and BestStacked hasn't verified either figure.
A newsletter publisher cleans an old 40,000-address list before a relaunch, then adds the API to its sign-up form so typos and disposable addresses are caught at entry.
AI scoring and Activity Data
Scoring costs one more credit per address and rates it from 1 to 10 on the likelihood of reaching a real inbox, which helps decide what to do with catch-all addresses that verification alone can't confirm. Activity Data, included with ZeroBounce ONE, shows which addresses had email activity in the past 30 to 180 days.
A B2B marketer keeps catch-all addresses scored 7 or higher and suppresses the rest instead of deleting every catch-all contact.
Warmup, inbox placement and server tests
ZeroBounce ONE bundles domain warmup (250 warmup seeds at the $99 starting configuration), 100 inbox placement tests to see whether a test email lands in the inbox or spam folder at major providers, and 100 email server tests that check authentication and DNS records. The free plan includes one inbox test and one server test; warmup isn't on the free plan.
A startup sending from a new domain warms it up for a few weeks and runs an inbox placement test before its first product announcement.
Blacklist and DMARC monitoring
ONE includes 10 blacklist monitors scanned every 8 hours and one DMARC monitor domain at its starting level; the free plan has one blacklist monitor scanned every 24 hours and no DMARC monitoring. DMARC monitoring reviews your SPF and DKIM alignment and reports on email sent using your domain, which helps spot spoofing.
An agency watches its own sending domain for blacklist listings and uses DMARC reports to find a forgotten tool that still sends as the company.
Feature recap
- Bulk upload and real-time API validation with detailed status codes
- Catch-all detection plus 1-10 AI scoring (1 extra credit)
- Email Finder at 20 credits per successful find
- Warmup, inbox placement and server tests (ONE plan)
- Blacklist and DMARC monitoring
- Unknown results and duplicates cost no credits
- 95 listed integrations, Zapier, Make, n8n and an MCP server
- SOC 2 Type 2, ISO 27001 and HIPAA (BAA) listed on its security page
The Numbers
ZeroBounce Pricing: Every Plan Explained
These are USD prices from ZeroBounce's pricing calculator on October 18, 2026, read in a browser. One credit validates or scores one address; an Email Finder result uses 20 credits. Checkout defaults to your region's currency, so local prices can differ.
| Plan | Monthly | Annual | Included Features | Best For |
|---|---|---|---|---|
| Freemium | $0 | $0 | 100 validation credits a month (business or premium email domain required), 1 inbox test, 1 server test, 1 blacklist monitor, 10 Email Finder searches; no Activity Data, warmup or DMARC | Trying the service or checking a few addresses |
| Pay-As-You-Go | From $39 for 2,000 credits | One-time purchases | 2,000 $39; 10,000 $129; 25,000 $274; 50,000 $499; 100,000 $649; 1,000,000 $3,199. Credits work for validation, scoring, Email Finder and Domain Search; purchases are non-refundable | Occasional list cleaning |
| ZeroBounce ONEBest value | From $99/mo (10,000 credits) | From $79/mo billed annually ($948/yr) | 10,000 credits a month plus 250 warmup seeds, 100 inbox tests, 10 blacklist monitors, 1 DMARC domain, 100 server tests, Activity Data, rollover credits, 15% off extra credits; 25,000 credits $199 ($159 annually), 100,000 $449 ($359) | Teams that verify every month and want deliverability tools |
| Enterprise | Contact sales | Contact sales | More than 1 million credits a month | High-volume senders and platforms |
Pricing scenarios (our calculations from ZeroBounce's published USD prices on October 18, 2026; tax excluded). Cleaning a 10,000-address list once costs $129 pay-as-you-go. One month of ZeroBounce ONE costs $99 for the same 10,000 credits plus the deliverability tools, and you can cancel before the next bill date, so a single month of ONE is cheaper than the credit pack if you remember to cancel. At 100,000 addresses the gap is wider: $649 pay-as-you-go against $449 for a month of ONE. Billed annually, ONE at 10,000 credits a month costs $948 a year, and its FAQ says unused credits roll over while you subscribe. Email Finder is expensive in credits: at 20 credits per successful find, 10,000 credits cover about 500 found addresses. Two rules matter before you buy. ZeroBounce's terms say credit purchases are final and non-refundable, and the ONE money-back guarantee applies only to a first subscription, within 30 days, and only if you've validated no more than 500 emails and stayed under small limits on the other tools, so it is effectively a refund for not using it. And for accounts registered after June 1, 2026, the terms say purchased credits expire two years after your most recent credit purchase unless a ONE subscription is active.
Read before you buy
Where ZeroBounce's pages differ
Credit expiry: the pricing page lists "Credits never expire" under "Included with all ZeroBounce Accounts" (zerobounce.net/pricing). ZeroBounce's terms of use (zerobounce.net/terms-of-use, "Credit expiration" clause) say credits purchased by customers who registered after June 1, 2026 expire two years after the most recent credit purchase, and stay valid only while a ZeroBounce ONE subscription is active. The pricing FAQ itself says "expiration rules may apply" without a subscription. Read on October 18, 2026; treat the terms as the binding version.
Subscription savings: the pricing FAQ says a subscription "can save you up to 18% every month" compared with pay-as-you-go. On the same page's calculator, 10,000 credits cost $99 on ONE monthly against $129 pay-as-you-go, about 23% less by our arithmetic, and 100,000 credits cost $449 against $649.
Accuracy guarantee: the homepage and pricing page say "99.6% Validation Accuracy Guaranteed", but we found no page that defines how accuracy is measured or what happens if it falls short, and a guess at a guarantee page (zerobounce.net/accuracy-guarantee) returned 404. Treat the figure as ZeroBounce's marketing claim.
Scoring
How the provisional score is built
BestStacked weights five sub-scores: ease of use 20%, features 25%, pricing 20%, support 15% and integrations 20%. For ZeroBounce they come only from ZeroBounce's own pages, not from testing, and they're provisional until the editor approves them. Ease of use 8.4: bulk upload, an API and native connectors for the common email and CRM tools, with a free tier to start; the credit rules (scoring, Email Finder at 20 credits, unknowns free) take some learning. Features 8.6: verification plus scoring, Activity Data, Email Finder, warmup, inbox tests, server tests, blacklist and DMARC monitoring in one account; the accuracy claim isn't independently substantiated on its pages. Pricing 7.8: a free tier, low-commitment credit packs and a ONE plan that undercuts its own packs, offset by higher per-credit prices than NeverBounce or Kickbox, non-refundable credits, a narrow refund window and conflicting expiry statements. Support 8.2: 24/7 chat, email and US and UK phone numbers are advertised, with VIP support on ONE. Integrations 8.6: 95 listed integrations including HubSpot, Mailchimp, Klaviyo, Salesforce, Zapier, Make and n8n, plus SDKs and an MCP server. That works out to 8.3 out of 10.
The Tradeoffs
ZeroBounce Pros and Cons
What we love
- Free account with 100 credits a month
- Unknown results and duplicates cost no credits
- ONE bundles warmup, inbox tests and blacklist and DMARC monitoring
- A month of ONE costs less than the same credits pay-as-you-go
- 95 listed integrations plus API, SDKs and an MCP server
- SOC 2 Type 2, ISO 27001 and HIPAA (BAA) listed
- 24/7 chat, email and phone support advertised
What could be better
- Credit purchases are non-refundable
- ONE refund ends after 500 validations
- Higher per-credit prices than NeverBounce or Kickbox
- Pricing page and terms disagree on credit expiry
- 99.6% accuracy is a vendor claim with no published method
- Email Finder uses 20 credits per result
The Audience
Who Should Use ZeroBounce?
Best for: email marketers who send every month
If you clean lists before each campaign and want to watch blacklists, DMARC and inbox placement, ZeroBounce ONE puts the credits and the monitoring in one bill from $79 a month billed annually.
Best for: product teams validating sign-ups
The real-time API, SDKs and integrations with HubSpot, Klaviyo, Mailchimp and form builders let you catch bad addresses at the point of entry, with unknown results not charged.
Skip if: you clean one list a year on a tight budget
For a one-off cleanup, NeverBounce ($8 per 1,000 credits) and Kickbox ($70 for 10,000) listed lower prices than ZeroBounce's $129 for 10,000 on October 18, 2026, and ZeroBounce won't refund credits once bought.
The Methodology
How We Reviewed ZeroBounce
This is an editorial review, not a hands-on test. BestStacked didn't use ZeroBounce for this review and makes no accuracy, speed or deliverability claims of its own; figures such as 99.6% accuracy and 100,000 addresses in 45 minutes are ZeroBounce's published claims. The review is based on ZeroBounce's own pages, all checked on October 18, 2026: the pricing page and calculator (read in a browser, monthly and annual, ZeroBounce ONE and Pay-As-You-Go at several credit levels), the homepage, the email validation, Email Finder and DMARC Monitor pages, the AI scoring documentation, the security page, the integrations directory (read in a browser), the contact page and the terms of use. Competitor prices come from each vendor's own pricing page the same day. Where ZeroBounce's pages differ, both versions are reported. BestStacked may earn a commission through ZeroBounce links; it does not affect the score.
Our editorial evaluation considers product information, official documentation, pricing, features and professional experience. It is not a claim of documented hands-on testing.
Our review methodology →What changed
- : First published. Editorial review based on ZeroBounce's pricing calculator (read in a browser), homepage, service pages, AI scoring docs, security page, integrations directory, contact page and terms of use, all checked October 18, 2026. Sub-scores are provisional until editor approval.
The Field
ZeroBounce vs The Competition
Prices below were read on each vendor's own pricing page on October 18, 2026, in USD. BestStacked hasn't reviewed these tools yet.
| Tool | Starting Price | Free plan | Best Feature | BS Score |
|---|---|---|---|---|
| ZeroBounce | Free 100 credits/mo; pay-as-you-go from $39 for 2,000 credits; ONE from $99/mo ($79/mo billed annually) | Yes | Bulk and real-time email validation | 8.3/10 |
| NeverBounce | $8 per 1,000 credits pay-as-you-go; Growth $49/mo for up to 10,000 | No | Low per-credit price for list cleaning | —No BestStacked review yet |
| Kickbox | 100 free; 10,000 for $70; 100,000 for $500 | Yes | Simple volume pricing | —No BestStacked review yet |
| Hunter | Free 50 credits/mo; Starter $49/mo ($34/mo billed yearly) | Yes | Email finding and outreach sequences | —No BestStacked review yet |
NeverBounce: NeverBounce sells pay-as-you-go credits at $0.008 each, which expire 12 months after purchase, and a Growth plan with CRM auto-sync and AI scoring. It offers free test credits and a free list analysis rather than a monthly free tier, and lists 80+ integrations.
Kickbox: Kickbox prices verification by volume, from $5 for 500 checks to $2,999 for 1 million, with 100 free verifications and no charge for unknown results. It focuses on verification rather than warmup or monitoring.
Hunter: Hunter is built around finding B2B addresses and sending outreach: a found email costs 1 credit and a verification 0.5. Starter includes 2,000 credits a month, and credits don't roll over.
In The Wild
How People Actually Use ZeroBounce
A newsletter relaunching an old list
A 25,000-address list costs $274 to clean pay-as-you-go, or $199 for a month of ZeroBounce ONE at 25,000 credits if you cancel before the next bill. Score the catch-all addresses before deciding what to keep.
A SaaS product validating sign-ups
Connect the real-time API to the sign-up form so typos and disposable addresses are rejected at entry. ONE at 10,000 credits a month ($79 billed annually) covers about 330 sign-ups a day, with unknown results not charged.
An agency managing client sending domains
Use ONE's blacklist monitors and DMARC reports on client domains and run inbox placement tests before big sends. Add domains and tools in the calculator; the $99 starting configuration includes one DMARC domain and 10 blacklist monitors.
The Ecosystem
ZeroBounce Integrations
ZeroBounce's integrations directory listed 95 integrations on October 18, 2026, plus an API, SDKs and Zapier for anything not listed.
- →HubSpot, Salesforce, Pipedrive, Zoho CRM and Microsoft Dynamics 365
- →Mailchimp, Klaviyo, ActiveCampaign, Brevo, MailerLite, Constant Contact and AWeber
- →Shopify, BigCommerce, WordPress, Wix, Unbounce and Instapage
- →Google Sheets, Microsoft Excel and Google Forms
- →Zapier, Make, n8n and Workato
- →Apollo, Clay and Outreach
- →ChatGPT and an MCP server for AI assistants
- →REST API with SDKs, browser extensions and an iOS app
The directory mixes native connectors, API hubs and browser extensions. Check the listing for your tool to see whether it supports real-time validation or only list syncs.
Common Questions
ZeroBounce FAQ
The Final Word
Should You Use ZeroBounce?
ZeroBounce is a sound choice when verification is a monthly habit rather than a one-off: the ONE plan undercuts its own credit packs and adds warmup, inbox placement tests and blacklist and DMARC monitoring that rivals sell separately or not at all. It integrates with most email and CRM tools and lists strong security certifications. Buy with the fine print in mind: credits aren't refundable, the subscription refund ends after 500 validations, the pricing page and terms disagree on credit expiry, and the 99.6% accuracy figure is ZeroBounce's claim, not an independent result. For cheap one-off cleaning, compare NeverBounce and Kickbox first. We score ZeroBounce 8.3/10, provisionally.
Yes, if
you verify lists or sign-ups every month and want deliverability monitoring from the same vendor
No, if
you clean one list a year and want the lowest price per check, or you need a refund after trying it on a real list
About the reviewer
Carlos Gil
Founder & Editor, The Best Network
Carlos Gil is the Founder & Editor of The Best Network, bestselling author of The End of Marketing, and a LinkedIn Top Voice. His digital marketing career began in 2008 and spans corporate roles at LinkedIn and BMC Software, consulting for global brands, creator partnerships, and building his own businesses.
Get the best of BestStacked
The AI tools worth knowing. None of the noise.
- New AI tool and software reviews as they publish
- Head-to-head comparisons and stack breakdowns
- The occasional recommendation worth knowing
No fake urgency. No made-up weekly cadence. Unsubscribe anytime.