Deliverability

Also called inbox placement

Deliverability is whether your email reaches the inbox at all, as distinct from whether it is opened.

Sending is not arriving. Between the two sit authentication checks, reputation scores and spam filters, and a message that fails them is never seen regardless of how good it is.

Reputation is built on how recipients behave. Opens, replies and time spent raise it; deletions without opening, and spam complaints, lower it hard. This is why continuing to mail people who never open damages the experience of the people who do.

The technical baseline is authentication — SPF, DKIM and DMARC records on your sending domain. Without them, major providers now reject or filter bulk mail outright.

In practice

Removing contacts who have not opened anything in six months typically raises open rate and inbox placement at the same time, despite a smaller list.

Common mistake

Keeping every address forever. Dormant contacts do not cost storage, they cost reputation, and the reputation is shared with your active readers.

Deliverability

In practice

Common mistake

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