Email Verification

Email Verification That Protects Your Sender Reputation

ListPlus is an email verification tool built for B2B lists. MX lookup plus SMTP handshake on every address, catch-all detection, disposable-domain filters, role-based email flagging — all in one API, bulk-capable up to 100,000 rows. Priced at €0.003 per verification on Pro, 50-80% cheaper with your own MillionVerifier or NeverBounce key on Premium.

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Free plan · MX + SMTP check · Catch-all detection · EU-hosted · GDPR-compliant
The Problem

Why unverified email lists destroy your sender reputation

Send to a dirty list once and your domain lands on Gmail and Outlook throttling lists. Recovery takes weeks. Most teams find out only after open rates collapse.

List Quality
15–30%
Typical invalid rate on uncleaned B2B lists

Scraped or aged lists often contain 15-30% invalid emails — bounces, catch-all traps, spam traps, role-based addresses. One send and mailbox providers start filtering your domain.

Blocklist Recovery
Weeks
Recovery time after blocklisting

Once Gmail or Outlook flag your domain as a spam source, recovery takes 2-4 weeks minimum — and many campaigns never recover their original deliverability.

Bounce Threshold
0.5–1%
Acceptable bounce rate threshold

Mailbox providers expect bounce rates under 1%. Above that, your domain gets throttled. Verification before send keeps you safely under the threshold.

Wasted Spend
€€€
Wasted outreach budget

Every email sent to an invalid address is wasted outreach-tool credits, wasted SDR time, wasted opportunity. Verification upfront costs a fraction of a bounce.

The Real Cost
One dirty campaign can kill deliverability for months — and you won't know until the opens collapse.

Verify every address before it ships. It's the cheapest insurance in outbound.

The Solution

Four-layer email verification — in one API call

ListPlus verification runs all four checks in parallel and returns a single aggregate result with per-check details. Bulk-capable via API, CSV upload, or CRM integration.

MX Lookup
Domain MX record check

First gate: confirm the email domain has valid MX records. Catches typo'd domains, dead domains, and misconfigured servers before the SMTP handshake even starts.

  • Real-time DNS query against authoritative nameservers
  • Flags dead domains immediately
  • Catches common typos (gmial.com, hotnail.com)
  • Zero cost for obvious failures
MX record lookup against authoritative DNS
SMTP Check
SMTP handshake without sending

Second gate: actual SMTP conversation with the mail server — RCPT TO check — to confirm the mailbox exists. No email is sent. Works even on servers that silently accept all mail (catch-all detection kicks in).

  • RCPT TO verification on verified MX host
  • No email sent, no inbox disturbed
  • Handles greylisting with retry logic
  • Flags catch-all domains separately
SMTP handshake verification without sending mail
Filters
Disposable + role-based detection

Third gate: filter out addresses that exist but shouldn't be contacted — disposable/throwaway services (mailinator, 10minutemail) and role-based addresses (info@, support@, sales@) that don't belong to a person.

  • 3,500+ known disposable domains tracked
  • Role-based email flagging (info, support, contact, etc.)
  • Customizable per-use-case filters
  • Free plan includes filter updates
Disposable and role-based email filtering
Catch-All
Catch-all domain detection

Fourth gate: detect domains that accept all mail regardless of whether the mailbox exists. These are technically deliverable but high-risk — ListPlus flags them so you can decide whether to include them.

  • Sends probe to verify catch-all behavior
  • Flags high-risk domains separately
  • Per-domain confidence score
  • Decide per segment whether to include
Catch-all domain detection with confidence scoring
Compare

ListPlus vs. ZeroBounce, NeverBounce, MillionVerifier

Standalone verifiers are good at verification but force you to re-import your list every time. ListPlus runs verification as part of the pipeline — after enrichment, before CRM sync.

ZeroBounce

Strong standalone verifier with AI scoring. Requires CSV exports and re-imports. ListPlus verification runs inside the enrichment waterfall — no round-trips.

NeverBounce

Fast, reliable verification API. Solid choice for pure verification, but no enrichment or CRM sync. ListPlus covers both plus bidirectional CRM sync in one flow.

MillionVerifier

Affordable per-verification pricing. Premium plan lets you plug your MillionVerifier API key into ListPlus and pay provider prices directly — 50-80% cheaper.

Hunter Verifier

Bundled with Hunter — fine if you already use Hunter for lookups. ListPlus cascades Hunter verification as one of several sources, falling back when coverage is weak.

Bouncer

Strong catch-all detection. ListPlus matches on catch-all behavior plus disposable detection, role-based flagging, and MX validation in a single call.

Kickbox

Enterprise-grade verification with a strict sender-score focus. ListPlus delivers similar quality plus integrations with HubSpot, Salesforce, Pipedrive, Sheets, and the AI Agent API.

Before / After

From dirty list to verified send-ready segment.

After ListPlus verification
✓<1% bounce rate, safe to send
✓Role-based addresses flagged separately
✓3,500+ disposable services filtered out
✓Catch-all domains flagged, decision is yours
✓Verification runs inside enrichment pipeline
✓One API, one credit system, one bill
Before verification
✗15-30% invalid addresses
✗Role-based emails mixed in with personal
✗Disposable domains land in your list
✗Catch-all traps hurt reputation
✗CSV export → verify → re-import cycle
✗Separate subscriptions for verifier + finder

Pricing — €0.003 per verification on Pro

Free plan includes 100 free verifications. Pro at €39/month covers 5,000 records with verification bundled in. Premium lets you use your own MillionVerifier or NeverBounce API key at provider prices.

See full pricing
FAQ

Email verification — frequently asked questions

What is email verification?
Email verification is the process of checking whether an email address is valid and safe to send to — without actually sending anything. ListPlus runs four checks per address: MX record lookup (does the domain accept mail?), SMTP handshake (does the mailbox exist?), disposable/role detection (is it the kind of address you should contact?), and catch-all detection (is the server accepting all mail regardless of mailbox?).
Why do I need email verification?
Sending to invalid addresses damages your sender reputation. Mailbox providers like Gmail and Outlook track bounce rates — above 1% and your domain gets throttled or blocklisted. Recovery takes weeks. Verification before every campaign keeps you safely under the threshold and protects the deliverability of every future send.
How accurate is email verification?
ListPlus runs full MX lookup plus SMTP handshake on every address, matching the accuracy of dedicated verifiers like ZeroBounce and NeverBounce — typically 97%+ accurate. Catch-all domains are flagged separately because no verifier can definitively confirm catch-all deliverability — only the mail server knows.
Can I verify emails in bulk?
Yes. Paste up to 100,000 addresses, upload a CSV, connect a Google Sheet, or call the API. ListPlus runs verification in parallel with provider rate limits respected. Results come back with per-address status (valid, invalid, catch-all, role-based, disposable) plus a single aggregate score per row.
How does catch-all detection work?
A catch-all domain is one that accepts mail for any address — valid or not. ListPlus sends a probe to a random address at the domain. If it's accepted, the domain is flagged catch-all and your result is marked 'deliverable but risky'. You decide whether to include catch-all domains in your send segment or exclude them for safety.
Does ListPlus detect disposable email addresses?
Yes. ListPlus tracks 3,500+ known disposable and throwaway email services (mailinator, 10minutemail, guerrilla mail and many more). Addresses at these domains are flagged 'disposable' so you can exclude them from outreach automatically.
How does email verification pricing work?
Free plan includes 100 verifications. Pro at €39/month includes verification bundled into the 5,000-record allowance — no separate charge. Premium at €79/month lets you plug in your own MillionVerifier, NeverBounce, or Kickbox API key and pay provider rates directly (typically 50-80% cheaper than managed pricing).
Is email verification GDPR-compliant?
Yes. Verification runs in Frankfurt on AWS eu-central-1. Addresses are processed in the EU and auto-deleted after verification — only the aggregate result is stored (for 30 days, to prevent duplicate checks). ListPlus is data processor per GDPR Art. 28 with a standard DPA available on Premium.

Clean your list before the next send.

100 free verifications. No credit card. MX + SMTP + catch-all in one API. EU-hosted.

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