Apollo vs BillionVerify for Email Verification

Apollo's confidence score reflects pattern matching at the time of data collection. It is a data quality signal, not a real-time deliverability check. Even addresses with 90%+ confidence can include mailboxes that have since closed, catch-all domains where delivery is uncertain, and role-based addresses that route to shared inboxes. BillionVerify runs its SMTP check at the moment of import, which catches changes that occurred between Apollo's last update and your send date.

There is no confidence threshold that eliminates the need for verification. Even 90%+ confidence addresses can produce bounces if the employee left the company or the domain changed configuration. If you need to reduce list size before verification, use the confidence score as a pre-filter — but always run the remaining list through BillionVerify before any send.

Apollo notes catch-all domains in its exports. BillionVerify confirms catch-all status at the SMTP level and places those addresses in a separate result category. Do not send catch-all addresses through high-volume sequences alongside confirmed valid addresses. Route them to a separate, lower-volume segment and monitor engagement carefully to avoid compressing your sender reputation.

Yes. Any Apollo export older than 90 days should go through BillionVerify again before reuse. Addresses that were valid when you last ran verification may have changed. Apollo does not update saved lists automatically when underlying contact data changes.

Apollo's verification is part of its internal data quality process — it scores addresses based on patterns and historical data. BillionVerify is an independent check that connects directly to the receiving mail server. The two checks are complementary: Apollo tells you the address pattern is plausible, BillionVerify confirms the mailbox accepts delivery right now. Running both gives you higher send confidence than either alone.

BillionVerify identifies role-based addresses — info@, sales@, support@, hello@ — and returns them as a separate result category. Apollo exports sometimes include role-based addresses when contact data is incomplete or when a domain search returns generic company addresses. BillionVerify flags these so you can route them to a separate campaign with messaging appropriate for shared inboxes, rather than treating them as individual contacts.

Yes. Re-verify any Apollo export that is more than 90 days old before reusing it. Apollo does not automatically update saved lists when the underlying contact data changes. An address that verified as valid on your last campaign may now be invalid, catch-all, or role-based due to changes at the company since that verification was run.

The core workflow is the same — export from the source tool, verify with BillionVerify, route by result. The difference is in the source tool's method. Apollo uses a large database with confidence scoring; Hunter uses domain pattern matching with a built-in verifier. Both produce exports that benefit from an independent SMTP check. See Hunter vs BillionVerify for how that specific comparison differs.

Apollo's sequence tool sends to the addresses in your list without a final SMTP gate. If those addresses include stale records, catch-all domains, or role-based inboxes, Apollo will attempt delivery to all of them. BillionVerify sits before import — removing or segmenting the addresses that should not enter the sequence at all. This protects your sender domains from absorbing bounces and complaint signals before the campaign produces any useful signal.