Short, practical writing on getting mail to the inbox. Hygiene, authentication, warmup, reputation, and the signals that decide placement before a single recipient ever sees the subject line.
The decision between your inbox and the spam folder is made in a fraction of a second, by a machine that will never read what you wrote. Understanding its rubric is the only durable way to get out, and stay out.
Three acronyms decide whether your mail arrives with a green tick or a red flag. None of them are complicated. All three have to agree, and all three have to be set up in the right order.
A fresh domain has no reputation. To inbox providers, a new domain sending ten thousand messages on day one is indistinguishable from a spam operation. Warmup is the ritual that tells providers, slowly and with evidence, that this is a real sender.
A catch-all accepts mail for every address it is offered, real or not. That single property is why verification services cannot always give a clean yes or no, and why a list of catch-all addresses behaves differently from the rest of your file.
Postelist catches invalid addresses, typos, and spam traps before they reach your send file. Upload a CSV, or check each new signup as it arrives. Start with 100 free verifications — no credit card required.
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