Keep a list healthy between campaigns

Re-check old addresses, suppress bounces, and track list quality over time.

Fig. 1Re-check schedule

§ 1

Why it matters

Cleaning once is not enough

Lists decay every month. A single clean-up only resets the clock.

A short routine that keeps bounce rates low all year.

§ 2

How it works

Check new contacts as they arrive, re-check old ones on a schedule, and suppress every bounce and complaint.

Fig. 2A simple routine

What to do

§ 3

What you get

3.1Track list qualityCompare the list quality score from month to month.
3.2Find the bad sourcesIf one form or vendor brings in most invalid addresses, fix the source.

Table 3 · Suppression reasons

Reason	How the address got on the list
bounce	Your email platform reported a bounce.
complaint	The recipient marked a message as spam.
unsubscribe	The recipient unsubscribed.
invalid	A check found the address invalid.
auto_invalid	Added after a check, from your workspace settings.
spam_trap	The address is at a known spam-trap domain.
manual	Someone on your team added it, or imported a file.

§ 4

In practice

Case 4.1
Before a big send
Re-check the full list a day before a launch or a holiday campaign.

Questions

How often should I re-check?

Every 30 to 90 days for active lists, and always before you send to addresses you have not mailed in months.