What is greylisting? A Plain-English Guide
Greylisting temporarily rejects mail from unknown senders with a soft error, expecting legitimate servers to retry. It delays but rarely blocks properly configured senders.
Why it matters for deliverability
Understanding greylisting is part of why some mail is delayed, not lost. Get it right and more of your mail reaches the inbox; get it wrong and even legitimate mail can be filtered.
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How Rainmail helps
Rainmail sends from your own domain on a dedicated, isolated IP with SPF, DKIM, DMARC, reverse-DNS and managed warm-up handled for you, plus an AI that watches your list health and deliverability — and it welcomes the senders Amazon SES, SendGrid and Mailchimp reject, from $8. Run the free 10-second checker or see plans.