Verifying School District (K-12) Email Addresses: Teachers, Admins and Student Accounts

K-12 addresses can usually be verified for staff, but you should only target staff. Districts commonly host mail on Google Workspace or Microsoft 365, sometimes behind a filter, and the result you get depends on that setup. Paste a few staff addresses into the verify page to see which kind a district is.

What a check returns on a district domain

Setup	Result	Reason you will see
Server rejects unknown users	Valid or invalid	Mailbox exists or Mailbox not found
Server or filter accepts everything	Risky	Accepts all addresses
Server refuses our check	Risky	Server refused our check

For the Google and Microsoft cases the same rules apply as for companies. See Google Workspace catch-all domains and checking Microsoft 365 company domains.

Student accounts are a different problem

Student mailboxes are commonly locked down. Districts often limit them to internal mail, so a message from outside is refused even when the mailbox exists. That produces rejections like those in recipient only accepts internal mail. More importantly, these are minors. Do not build a campaign around them. Aim at teachers, department heads, principals, technology coordinators and district office staff.

Finding the right staff addresses

Use the district's published directory, not guesses. Districts commonly publish staff pages. Pull addresses from there, then verify them. A guessed pattern that works for most staff will still miss some, and on a domain that accepts everything you cannot tell right from wrong. See how to find email addresses on a website.

Timing

Summer and the new school year are when accounts change. Staff are reassigned, new hires arrive and some accounts are retired. A list built last spring will have gaps by autumn. Verify close to the send, and re-verify older files. The wider effect of age on lists is covered in how fast B2B contact data decays.

What a check cannot tell you

• Whether the district filter will deliver your message.
• Whether a student account takes outside mail.
• Whether the person is still in the role.
• Whether a guessed address belongs to a real employee.

Verify your school list

The first 100 email checks on the verify page are free with a Google sign-in, no card. Each comes back valid, risky or invalid with a reason, and nothing is sent to anyone on the list. For a bigger file, see bulk email verification, list cleaning and pricing.