Sender deliverability

Register and build your sending reputation

Mailbox providers do not offer a universal IP registration or guaranteed inbox placement. Their sender portals help you verify ownership, monitor reputation, receive complaint data, and correct delivery problems while your domain and IP earn trust through legitimate email.

Before registering

Complete the SMTP Server for WordPress DNS and server checks first. Your sending hostname must resolve to the sending IP, the IP’s PTR must resolve back to that hostname, and SPF, DKIM, and DMARC must validate. Registration cannot compensate for missing authentication.

Register with the major mailbox providers

Google Postmaster Tools

Add the domain used by your DKIM signature or SPF Return-Path. Google discovers associated sending IPs from authenticated Gmail traffic. Low-volume senders may not immediately see dashboard data.

Read Google’s setup instructions

Microsoft SNDS

Request access to each public sending IP you control. Smart Network Data Services shows Outlook.com reputation data and includes the Junk Email Reporting Program for recipient complaint reports.

Yahoo Sender Hub

Add and verify your DKIM signing domain, then enroll it in Yahoo’s Complaint Feedback Loop. Complaint reports help you suppress recipients who mark messages as spam.

Yahoo Complaint Feedback Loop

FastEmailServers main relay example

Sending domainfastemailservers.com
Sending IP15.204.83.156
Mail hostname and PTRsmtp01.fastemailservers.com

If you operate a different server or send for a different domain, register the domain and public IP shown by your own SMTP Server for WordPress installation.

Warm up a new IP responsibly

  • Start with small, consistent volumes sent only to recipients who expect the messages.
  • Avoid bursts, purchased lists, repeated synthetic tests, and sudden volume increases.
  • Keep the sending IP, hostname, PTR, DKIM identity, and From domain stable.
  • Process hard bounces, unsubscribes, and complaint reports promptly.
  • Use recognizable sender names, accurate subjects, and complete transactional content.
  • Monitor provider responses and slow down when a mailbox provider returns temporary rate limits.

Google does not provide sender IP allowlisting or exceptions. Reputation is earned over time through authenticated, wanted, consistently sent email.

Google: IP authorization and allowlisting · Google sender guidelines

Provider enrollment does not guarantee inbox placement. Each mailbox provider evaluates authentication, complaints, engagement, sending consistency, message content, domain reputation, IP reputation, and other abuse signals.