Gmail, Yahoo and Microsoft Sender Requirements Explained
inboxy team · · 3 min read
In February 2024, Gmail and Yahoo started enforcing new rules for anyone sending email at volume. In May 2025, Microsoft followed for Outlook.com, Hotmail and Live addresses. Together they cover most inboxes your prospects use, and mail that breaks the rules is increasingly sent to spam or rejected. Here is what each one requires, in plain words.
The rules at a glance
| Requirement | Gmail | Yahoo | Microsoft |
|---|---|---|---|
| SPF | Required | Required | Required for bulk senders |
| DKIM | Required | Required | Required for bulk senders |
| DMARC (p=none is enough) | Bulk senders | Bulk senders | Bulk senders |
| From domain aligned with SPF or DKIM | Bulk senders | Bulk senders | Bulk senders |
| One-click unsubscribe | Marketing mail | Marketing mail | Recommended |
| Spam complaint rate | Below 0.3%, aim for under 0.1% | Below 0.3% | Keep low |
"Bulk sender" means roughly 5,000 or more messages a day to that provider's addresses. Gmail counts all mail from your primary domain together, so many small inboxes on one domain can add up.
Gmail
- Everyone needs SPF or DKIM, valid forward and reverse DNS, TLS, and a spam rate below 0.3% in Google Postmaster Tools.
- Bulk senders also need SPF and DKIM, a DMARC record (p=none is acceptable), alignment between the From domain and SPF or DKIM, and one-click unsubscribe on marketing and subscribed messages.
- Google recommends keeping spam complaints under 0.1%. Approaching 0.3% hurts delivery significantly.
Yahoo (and AOL)
Yahoo's rules mirror Gmail's: authenticate with SPF and DKIM, publish DMARC, keep complaints below 0.3% and honour unsubscribes within two days, with one-click unsubscribe for marketing mail.
Microsoft Outlook
From May 2025, Microsoft requires domains sending more than 5,000 emails a day to Outlook.com, Hotmail.com and Live.com addresses to pass SPF, DKIM and DMARC (at least p=none, aligned with SPF or DKIM). Non-compliant mail is sent to Junk, and Microsoft has said it will move to rejecting it. It also recommends working unsubscribe links, list hygiene and a valid From address.
What this means for cold email
Most cold emailers send far below 5,000 a day per domain, but treat the bulk rules as the minimum anyway:
- Set up SPF, DKIM and DMARC on every sending domain. Unauthenticated mail is the first thing filters punish. See our setup guide and the deep dives on DMARC and DKIM.
- Keep complaints low. Tight targeting and an easy way to opt out ("reply 'no' and I won't follow up") protect your complaint rate.
- Spread volume across several domains and inboxes rather than pushing one domain toward the bulk threshold.
- Monitor. Google Postmaster Tools shows your domain's spam rate and reputation for free.
Checking your setup
Send a test email to our free inbox placement test to see whether SPF, DKIM and DMARC pass and where your email lands.
Skip the setup
inboxy creates Google Workspace mailboxes with SPF, DKIM and DMARC already configured, connects them to your sequencer for free and keeps them warm, at a flat $3 per mailbox a month. See pricing.
