If someone hands you an email list, the first rule is simple:
do not treat it like a trusted send file yet.
Inherited lists come with missing context:
- how they were collected
- whether consent was clear
- when they were last used
- whether they were ever cleaned properly
Step 1: do not send immediately
The fastest way to hurt deliverability is to assume an inherited list is healthy.
Treat it as unverified data until you have evidence otherwise.
Step 2: understand what you inherited
Before cleaning, ask basic questions:
- How old is the list?
- Where did it come from?
- Has it been used recently?
- Was it ever maintained consistently?
Even partial answers help you interpret what you will find.
Step 3: clean before first use
Run the list through MailCull and get a status breakdown before any campaign touches it.
That lets you:
- remove undeliverable
- isolate risky
- decide whether the remaining list is strong enough to use
Step 4: restart cautiously
Even after cleaning, inherited data deserves a careful restart. Use smaller sends first and watch the outcome instead of assuming the whole audience should be blasted immediately.