Allowlisting 15Five's domains and IP addresses ensures that 15Five notification and invitation emails reach employees' inboxes rather than being filtered as spam. When complete, 15Five emails from the domains and IP addresses listed below will pass your organization's email filters.
Before You Begin
- This task requires access to your organization's email filtering or spam protection system. Your IT team must complete or approve these changes.
- If your organization uses 15Five Engagement, also see Add engagement survey emails, IP addresses, and URLs to your allowlist for Engagement-specific values.
Steps
- Open your organization's email filtering, spam protection, or firewall allowlist settings.
- Add the following sending domain to your allowlist:
mail.15five.com - Add the following wildcard domain to your allowlist:
*.15five.com - If your email service requires IP-level allowlisting, add the following IP addresses:
- 168.245.126.93 - 167.89.92.147
- Save your changes.
Note: These domain and IP values do not change on a scheduled basis. If 15Five updates these values, you will be notified through the 15Five Help Center and release notes.
Confirm It Worked
Send a test 15Five invitation email to an internal address after saving your changes. The email arrives in the inbox rather than the spam or junk folder.
If Something Goes Wrong
| Issue | Check | Fix |
|---|---|---|
| Test email still lands in spam after allowlisting | Confirm all four values were saved correctly in the allowlist settings | Re-enter each domain and IP address and save again |
Wildcard domain *.15five.com is not supported by your email filter |
Verify whether your email system supports wildcard entries | Add 15five.com as a literal domain instead, then contact your email filter vendor for wildcard support guidance |
| IP-level entries are rejected or cause conflicts | Confirm the IP addresses match exactly as listed in Step 4 | Remove and re-add each IP address individually; contact 15Five Support if the correct third IP address is needed |
Note: If emails still do not arrive after completing all steps above, contact your email service provider — further diagnosis requires access to mail server logs outside 15Five.
Not Covered Here
This article does not cover allowlisting for SSO/SAML, firewall rules, or Engagement-specific email addresses. See Add engagement survey emails, IP addresses, and URLs to your allowlist for Engagement values.