Email Deliverability for SaaS: SPF, DKIM, DMARC Setup and Resend Integration

Your transactional emails (receipts, password resets, notifications) landing in spam is catastrophic for a SaaS. SPF, DKIM, and DMARC are the technical foundation of email deliverability. Here's the exact setup to get into the inbox. Why Emails Go to Spam Email providers use two factors to decide deliverability: Reputation: Does your sending domain/IP have a history of sending good mail? Authentication: Can the receiving server verify you actually sent this email? SPF, DKIM, and DMARC are all about authentication. Without them, your emails look like potential spam regardless of content. SPF (Sender Policy Framework) SPF is a DNS TXT record that says which servers are allowed to send email from your domain. # DNS TXT record for yourdomain.com v=spf1 include:_spf.resend.com include:sendgrid.net -all Breakdown: v=spf1 -- SPF version include:_spf.resend.com -- Resend is allowed to send on your behalf include:sendgrid.net -- SendGrid is allowed -all -- fail (reject) mail from anyone else Us