Email Verification for Marketing Agencies - Protect Client Deliverability | BounceZero
Built for Marketing Agencies

Client Campaigns That Actually Deliver.

One bad list from a careless client can burn your agency sender reputation and tank all your other campaigns. BounceZero verifies every list before it touches a sending domain.

99.8%
Verification accuracy
< 0.5%
Bounce rate on cleaned lists
1M
Addresses per dashboard job
$3
Per 1,000 verifications

Your Reputation. Their Lists.

Agencies carry a risk no in-house team faces: you send from shared infrastructure on behalf of clients whose list hygiene you didn't control. One bad upload affects everyone.

One Client Burns All Clients

A single client list with a 10% bounce rate can push your shared sending domain onto blocklists - tanking deliverability for every other campaign your agency runs that week.

Client Lists Decay Fast

Email lists decay at roughly 22% per year. That "fresh export" a client hands you was pulled from a CRM last touched in 2023. Verifying before launch is the only safe assumption.

Catch-Alls Hide the Damage

Around 23% of B2B domains are catch-all - they accept everything at SMTP time, then bounce or spam-trap later. Basic verifiers pass them; BounceZero runs a 3-probe catch-all analysis.

6 Checks on Every Address, Every List

Whether it's a 500-row founder list or a 500,000-row enterprise export, every email goes through the same six-layer verification pipeline.

Mailbox Existence

Live SMTP-level confirmation that the mailbox actually exists - not just that the domain accepts mail.

Catch-All Detection (3-Probe)

Triple-probe analysis flags catch-all domains that would silently inflate a client's "valid" numbers.

Role Address Detection

Flags info@, sales@ and admin@ addresses that hurt engagement metrics and trigger spam complaints.

Disposable Email Detection

Catches throwaway addresses from temp-mail services that pollute client signup lists.

MX Record Validation

Confirms the domain has valid, reachable mail servers before a single send is attempted.

Spam Trap Detection

Identifies likely spam traps - the addresses that get agency sending domains blocklisted overnight.

The Agency Workflow

Make verification a standard step in your campaign launch checklist - from client handoff to clean send in minutes.

1

Collect the Client List

Client sends their CSV - CRM export, event scans, purchased data, whatever lands in your inbox.

2

Upload to BounceZero

Drag and drop up to 1,000,000 addresses per dashboard job, or push lists programmatically via the API.

3

Verification Runs

All 6 checks run on every address. A 10K list finishes in 5-10 minutes.

4

Review Per-Client Results

Download segmented results - valid, risky, invalid - and share the hygiene report with your client.

5

Launch With Confidence

Load only verified addresses into the sending platform. Cleaned lists bounce under 0.5%.

Pricing That Scales With Your Client Roster

No per-seat fees. No client caps. Pay only for verifications - and bill it straight through as a line item on your retainers.

Try It Free

100 verifications/month

No credit card required. Test the accuracy on a sample of your trickiest client list before committing.

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Pay As You Go

$3 per 1,000 emails

A 50K-subscriber client list cleaned for $150. Compare that to the cost of a blocklisted sending domain mid-campaign.

See Bulk Pricing

Not sure what dirty lists cost you? Run the ROI calculator.

New to verification? Start with the complete email verification guide.

Frequently Asked Questions

What marketing agencies ask before making BounceZero part of their launch checklist.

Why do marketing agencies need email verification more than in-house teams?

Agencies send on behalf of multiple clients, often from shared domains and IPs. One client's dirty list can damage deliverability for every account you manage. Verifying each list before launch isolates that risk - a cleaned list keeps bounce rates under 0.5%, well below the thresholds ESPs monitor.

Can I verify lists for multiple clients separately?

Yes. Each list is a separate bulk job with its own downloadable results, so you can keep per-client segmentation clean and share the hygiene report with each client. Dashboard jobs support up to 1,000,000 addresses, and a 10K list processes in about 5-10 minutes.

How accurate is BounceZero compared to other verifiers?

BounceZero delivers up to 99.8% accuracy in internal testing on SMTP-verifiable addresses, versus an industry benchmark of around 95%. On a 100,000-email client list, that difference is roughly 4,800 misclassified addresses - bounces you'd otherwise send into, or valid leads you'd otherwise throw away.

What about catch-all domains on B2B client lists?

Around 23% of B2B domains are catch-all, meaning they accept any address at SMTP time. BounceZero runs a 3-probe catch-all analysis to determine deliverability confidence instead of blindly marking these addresses valid, which is where cheaper verifiers quietly fail.

Can I automate verification into our campaign workflow?

Yes. The BounceZero API responds with timing that varies by provider and verification path on average, so you can verify addresses in real time at form capture or push entire lists programmatically before every send. Full documentation is available on the API docs page.

How much does it cost to clean a typical client list?

Pricing is $3 per 1,000 verifications with no subscriptions or seat fees. A 25,000-contact client list costs $75 to fully verify - and you get 100 free verifications every month to test with, no credit card required.

Never Let a Client List Burn Your Domain Again

up to 99.8% accuracy in internal testing on SMTP-verifiable addresses. $3 per 1,000 verifications. Results in seconds. Start with 100 free verifications every month - no credit card required.

Email verification by industry

Tailored use cases across teams and sectors

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