The Unglamorous Work That Decides Whether Email Arrives

You can write the best campaign of your career and have it land in spam. Deliverability is decided by mechanics that have nothing to do with the copy.

One-click unsubscribe is not optional

Since 2024, Gmail and Yahoo require bulk senders to include one-click unsubscribe headers. Not a link in the footer — the headers, so the mail client can offer it directly. Without them, mail from a high-volume sender gets throttled or foldered regardless of how good it is.

Growth7 adds both headers on every marketing send and hosts the unsubscribe itself, so the opt-out is recorded against the company rather than lost inside a provider account you might one day migrate away from.

Suppression has to be checked at send

An unsubscribe list nobody consults is decoration. The suppression check belongs in the send loop, before the message goes out, every time. A person who opted out in March should be skipped in September without anyone remembering to filter the list.

Warm-up is not superstition

A domain with no sending history that suddenly sends fifty thousand messages looks exactly like a compromised domain. Providers respond accordingly.

Volume has to build. Start small, increase gradually, and watch what bounces. A daily cap is not a limitation of the software — it is the mechanism that keeps a large list from destroying the reputation you need to send to it.

Never-subscribed is the loudest signal

A list of contacts who never opted in will produce complaints at a rate that no amount of warm-up survives. Where the addresses came from matters more than how carefully you send to them.

Segment on consent. Send to the people who asked. It is slower, and it is the only version that still works in a year.