Email deliverability is whether your messages reach the inbox instead of spam. The foundation is authentication: SPF, DKIM and DMARC records in your domain’s DNS that prove your email really comes from you. Since 2024, Google and Yahoo have required bulk senders to authenticate, offer easy one-click unsubscribes and keep spam complaints low.
The three records in plain words
- SPF lists the services allowed to send email for your domain.
- DKIM adds a digital signature that proves a message was not altered and came from an authorized sender.
- DMARC tells inbox providers what to do with mail that fails SPF or DKIM, and sends you reports.
| Record | Lives in | Example | Job |
|---|---|---|---|
| SPF | DNS TXT on your domain | v=spf1 include:_spf.google.com include:sendgrid.net ~all | Lists the services allowed to send as you |
| DKIM | DNS TXT at selector._domainkey | Public key from your email provider | Proves the message was not altered |
| DMARC | DNS TXT at _dmarc | v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com | Sets policy and sends you reports |
A deliverability checklist
- Set up SPF and DKIM for every service that sends as your domain: your email host, CRM, newsletter tool and invoicing software.
- Publish a DMARC record, start with monitoring, then move to quarantine or reject.
- Send marketing email from a subdomain if volume is high, to protect your main domain.
- Include a one-click unsubscribe in marketing emails.
- Remove bounces and long-inactive contacts regularly.
- Never buy lists.
Watch the signals
Monitor spam complaint rates in Google Postmaster Tools, bounce rates in your email platform and DMARC reports. A sudden drop in open rates is often a deliverability problem, not a content problem.
Frequently asked questions
Do small businesses need DMARC?
Yes. It protects your domain from spoofing and helps legitimate email get delivered.
Why did my emails start going to spam?
Common causes: missing authentication, a new sending tool not added to SPF, a spike in complaints or a list with many invalid addresses.
We check authentication whenever we connect a CRM or email platform for a client.
