Email delays when testing the customer account login process on my store (Version 2) in Gmail

Technical Q&A

Topic summary

  • Issue: Verification-code emails for customer login tests are delayed when sent to Gmail from a Shopify store (Version 2).
  • Observation: Emails appear as sent via the subdomain mailer3pk.[mydomain].com; the poster suspects this may be causing delays.
  • Goal: Have emails show as sent directly from [mydomain].com instead of mailer3pk.[mydomain].com.
  • Proposed approach: Use a custom SMTP (Simple Mail Transfer Protocol) configuration to send through their own domain to improve delivery speed.
  • Constraint: Acknowledges Shopify’s admin does not support SMTP setup.
  • Request: Looking for any workaround or alternative to avoid the mailer3pk subdomain and speed up delivery.
  • Status: No solution or consensus yet; inquiry remains open.
Summarized with AI on December 14. AI used: gpt-5.
1

I’m experiencing email delays when testing the customer account login process on my store (Version 2). Specifically, emails containing verification codes sent to Gmail are delayed.

I’ve noticed that the emails show: mailer3pk.[mydomain].com

I suspect that this mailer3pk subdomain may be contributing to the delays.

Is there a way to prevent emails from being sent via the mailer3pk subdomain and have them appear as sent directly from my domain (i.e., [mydomain].com) instead?

I would like to set up a custom SMTP configuration for sending emails through my domain to improve delivery speed, but I understand that Shopify currently does not offer SMTP setup in the admin. Is there any workaround or alternative solution to achieve this?

2

Google enforces strict authentication records. So there’s a process for that. Did you authenticate the domain in Settings → Notifications → Sender authentication and add the required CNAME records to your DNS provider? If you haven’t set all that up, you should probably check that out.

3

I already set CNAME and other DNS config.
I got message “Domain successfully authenticated” in shopify Sender authentication section.
I can received email in inbox, but it is delayed for a reason it Gmail.