Email deliverability
What is email deliverability?
Email deliverability is the ability of your emails to land in recipients’ inboxes instead of their spam folder or not at all. It depends on authentication (SPF, DKIM, DMARC), the reputation of your domain and sending servers, your bounce rate and spam complaints, and how recipients engage.
Delivery (the receiving server accepted the email) is not the same as deliverability (it reached the inbox).
Why email deliverability matters
An email in spam is an email nobody reads. Poor deliverability can also affect every email from your domain, including invoices and password resets.
How to improve email deliverability
- Set up SPF, DKIM and DMARC for your sending domain.
- Use a separate domain or subdomain for outreach so your main domain’s reputation is protected.
- Warm up new domains gradually.
- Verify addresses before sending to keep bounces low.
- Send relevant emails to people likely to want them, and honour opt-outs immediately.
- Watch bounce and complaint rates and slow down if they rise.
Related marketing terms
An SPF record is a DNS entry listing which servers may send email for your domain, so receivers can reject forged messages.
DKIM (DomainKeys Identified Mail)
DKIM adds a cryptographic signature to your emails, published in DNS, so receivers can verify the email came from your domain unaltered.
DMARC is a DNS policy telling receivers what to do with email that fails SPF or DKIM for your domain, and where to send reports.
Email warm-upGrey hat
Email warm-up is gradually increasing how many emails a new domain or address sends, so mailbox providers learn to trust it.
Email bounce rate is the share of sent emails that could not be delivered, because the address is invalid or the receiving server refused them.
Spam traps are email addresses used to catch senders with poor list practices. Hitting them can damage your domain’s sending reputation.