Should I verify emails before every send?

Usually, no—you generally should not verify emails before every send.

A better approach is:

• Verify once at capture: when a user signs up, submits a form, or is imported.
• Re-verify when needed: if an email bounces, changes, or has been inactive for a long time.
• Validate format every time: make sure the address is syntactically valid before sending.
• Use suppression lists: don’t keep retrying obviously bad or bounced addresses.

Why not verify every time?

• It adds latency to sending.
• It can be expensive, especially at scale.
• Real-time verification services are not always fully reliable.
• It can create a poor user experience for transactional emails.

When it does make sense to verify before sending:

• High-value sends where deliverability matters a lot
• New or risky lists
• Marketing campaigns to older/untrusted data
• Before sending to a contact after a long inactivity period

Best practice:

1. Syntax check
2. Domain/MX check
3. Mailbox verification at collection time
4. Monitor bounces and complaints
5. Re-check only risky addresses

If you want, I can suggest a practical email verification policy for transactional vs marketing sends.