Solution

Clean an old email list

Do not send to a list you have not used in 2+ months without verification. Protect your domain reputation.

Fewer hard bounces
Better deliverability
CSV in minutes

Why are old lists risky?

Addresses expire, people change jobs, domains go offline. The longer the gap between sends, the more invalid addresses accumulate — and ESPs treat hard bounces as a list quality signal, not a one-off error.

Self-serve: create an account, upload a list or connect the API without a sales call.

Signs of a dirty list

Rising bounce rate, falling open rate, and ESP warnings are signals that your database needs cleaning.

How do you verify an old list?

Choose the method that fits your database size and sending frequency. Most teams start with CSV in the dashboard, then move to bulk API for repeatable workflows.

CSV upload
Copy-paste
Bulk API
ESP integration (coming soon)

When to clean a list

Before every major campaign, after importing from a new source (webinar, event, partner), and every 3–6 months for regular sends. After a pause longer than 2 months, treat verification as mandatory.

Cost vs cost of a dirty list

One credit per address is a fraction of the cost of hard bounces to domain reputation, support time, and wasted ESP slots. Pre-send verification is the cheapest deliverability insurance.

Re-engagement and verification

Reactivation campaigns on an old database without an audit often end in a spike of hard bounces. Before you send “come back” to a list that is a year old, verify addresses and send only to valid. You can move risky contacts to a separate test segment with lower frequency and strict bounce monitoring.

Segmentation by verification status

A CSV export with a status column lets you build ESP segments without clicking through thousands of rows. Valid goes to the main campaign, invalid to deletion, risky to a policy that depends on your industry. Unknown is worth retrying in a bulk job or flagging for manual review before the first email.

Valid: full campaign or onboarding.
Invalid: remove from database and CRM.
Risky: separate segment or exclude in cold email.
Unknown: retry or short pause before sending.

Migration from CRM, spreadsheets, and many sources

Lists built from webinars, events, partners, and old CRM exports have the highest invalid rate. Before merging into one database, verify each import separately or the whole set after deduplication. We keep extra columns in the export so source tags and sales fields stay with the address.

Metrics after cleaning a list

After verification expect a lower bounce rate, a more stable open rate (fewer dead inboxes), and fewer ESP complaints. Monitor these metrics for 2–4 weeks after a campaign on the cleaned database — that is the best proof of ROI from a one-time list audit.

Re-importing into your ESP

After exporting CSV with a status column you import the list into Mailchimp, GetResponse, Brevo, or another ESP. Most platforms let you filter on a custom field — set a rule “send only when status = valid”. You do not have to delete thousands of contacts manually in the ESP UI; a segment or exclusion based on the verification label is enough.

GDPR and storing old lists

Cleaning a list is also a moment to audit consents and legal bases. Invalid addresses are worth removing so you do not process data unnecessarily. EmailVerifier export does not replace your privacy policy, but it helps document that you checked list quality before sending — useful with your DPO and when handling spam complaints.

Bounce thresholds that should trigger action

If bounce rate exceeds 2–3% on a transactional campaign or 1% on cold outreach, an ESP may throttle sending or require a list audit. An old database without verification often yields 5–15% hard bounce on the first email after a pause. Pre-send verification brings that down to a level most mail providers accept.

“We cleaned 40k leads before a cold email push. Bounce dropped from 9% to under 1% — domain reputation recovered.”
Marta, B2B SaaSVerified customer

“We upload a CSV from CRM every week. Export with statuses saves hours of manual checking.”
Tomasz, outbound agencyVerified customer

“Trial credits were enough to judge quality. Then we bought a pack for our B2B newsletter.”
Kamil, marketing automationVerified customer

Email list verification Bulk email verification Verification accuracy

Frequently asked questions

How often should you clean a list?

Before every major campaign and every 3–6 months for regular sends.

Do you remove invalid addresses from my list?

You export a CSV with status labels. You decide whether to delete them in your ESP or import via your mailing tool.

What about risky addresses?

Risky covers catch-all, disposable, and role-based mailboxes. In B2B campaigns you may keep them; in cold email it is safer to exclude them.