What Changed and Why
In February 2024, Gmail and Yahoo began enforcing stricter rules for people who send marketing email to their users. The goal was to reduce spam and spoofing by making senders authenticate their email, keep complaints low and offer easy unsubscribes.
Microsoft introduced similar requirements for Outlook.com, Hotmail and Live addresses from May 2025. Together, these providers handle a large share of personal inboxes, so the rules effectively set the baseline for anyone doing email marketing.
The strictest rules apply to high-volume senders, but the steps are good practice for everyone. We'd authenticate your domain, publish a DMARC record and keep complaints low from day one.
Who the Rules Apply To
The rules have two levels:
- All senders should authenticate with SPF or DKIM, have valid DNS setup, send over secure connections and keep spam complaints low.
- Bulk senders, which Google defines as sending around 5,000 or more messages a day to Gmail addresses, must also meet extra requirements. Microsoft uses a similar 5,000-a-day threshold for Outlook.com. Yahoo describes bulk senders more generally.
Once a domain counts as a bulk sender, it's generally treated that way going forward, so it's wise to meet the full set of rules before you grow.
The Requirements in Plain English
| Requirement | What it means | Applies to |
|---|---|---|
| Send from your own domain | Use an address like [email protected], not a free Gmail or Yahoo address | Effectively all marketing senders |
| SPF and DKIM | DNS records that prove your email platform may send for your domain | All senders (both for bulk senders) |
| DMARC | A DNS record telling inboxes how to treat mail that fails checks; a policy of "none" is the minimum | Bulk senders |
| Alignment | The domain in your From address matches the domain that passes SPF or DKIM | Bulk senders |
| One-click unsubscribe | A special email header that lets inboxes show an unsubscribe button, plus a visible link in the email | Bulk senders' marketing email |
| Honor unsubscribes quickly | Process unsubscribe requests within two days | Bulk senders |
| Low spam complaints | Keep the rate of people marking you as spam below 0.3%, ideally under 0.1% | All senders, strictly for bulk |
Providers update their guidance from time to time, so check the current versions of Google's, Yahoo's and Microsoft's sender guidelines for details.
What Happens If You Don't Comply
Mail that doesn't meet the requirements may be sent to spam, rate-limited or rejected outright. Problems often show up as a sudden drop in opens and clicks from Gmail, Yahoo or Outlook addresses, or bounce messages mentioning authentication.
The spam complaint threshold is the one many senders underestimate. Even a fully authenticated sender can struggle if too many people mark their emails as spam.
Your Compliance Checklist
- Use a custom-domain sending address, such as [email protected].
- Authenticate your domain in your email platform with custom DKIM. See SPF, DKIM and DMARC setup.
- Publish a DMARC record starting with a policy of "none."
- Confirm one-click unsubscribe is included by your email platform and that every email has a visible unsubscribe link.
- Send only to people who opted in, and remove bounces and inactive subscribers. See email list hygiene.
- Monitor complaints with tools such as Google Postmaster Tools, and act if rates rise.
How AWeber Helps
AWeber requires a custom-domain sending address and walks you through authentication on its Domains and Addresses page. For supported DNS providers, it can add DKIM and DMARC records automatically; otherwise it shows the records to add yourself. AWeber's own guidance recommends starting DMARC with a policy of "none."
AWeber also handles unsubscribe links and processing for you. Your part is to collect permission properly and keep your list clean. See AWeber deliverability.
Keeping Complaints Low
- Remind people why they're hearing from you, especially in the first emails.
- Send what you promised, at the frequency you promised. See how often to send emails.
- Make unsubscribing easy. People who can't find the link press "spam" instead.
- Never use purchased lists. See buying email lists.
- Re-engage or remove inactive subscribers regularly. See re-engagement email campaign.
AWeber walks you through custom DKIM and DMARC and handles unsubscribes, so you can focus on emails people want.
Sender Requirements FAQs
What are the Gmail and Yahoo sender requirements?
Authentication with SPF and DKIM, a DMARC record, alignment, one-click unsubscribe and low spam complaint rates for bulk senders.
Do the rules apply to small senders?
The strictest rules target bulk senders, but all senders should authenticate and keep complaints low.
Can I send marketing email from a Gmail address?
Not reliably. Use an address on your own domain so you can authenticate it.
Does Outlook have similar requirements?
Yes. Microsoft began enforcing similar rules for high-volume senders to Outlook.com in May 2025.