Lists vs segments
One you fill yourself; the other fills itself from rules.
Both are ways of pointing a campaign at part of your audience, and you can use them together. The difference is who decides membership.
The difference
| List | Segment | |
|---|---|---|
| Membership | You add and remove people | Rules decide, continuously |
| Changes when | You change it | The underlying data changes |
| Good for | “Newsletter subscribers” | “Hasn’t clicked in 90 days” |
| Can trigger a flow | Joining or leaving it | Starting to match it |
A list is a folder you put people in. A segment is a saved question, answered fresh every time you look — so it’s never out of date, and nobody has to remember to maintain it.
Which to use
Use a list when membership is a decision: who signed up for which newsletter, who came to the September event, who your wholesale customers are. Signup forms add people to lists, and a list is what a welcome email hangs off.
Use a segment when membership is a fact you’d otherwise have to keep checking: everyone in London, everyone who has never opened anything, everyone whose renewal field is this month.
Most accounts end up with a handful of lists and a longer tail of segments, which is the healthy shape.
Using them together
A campaign can target any combination of lists and segments. The audience is everyone subscribed who appears in any of them, and anyone in more than one is counted — and mailed — once.
So “the Newsletter list plus everyone who clicked last month” is one campaign, not two, with no duplicate sends.
Narrowing rather than combining
To send to people who are in a list and match a rule, build a segment with a “is in list” rule in it. Picking both as targets widens the audience; putting the list inside the segment narrows it.
FAQs
Does deleting a list delete the contacts?+
No. It removes the grouping only — everyone stays in Contacts with their status and history intact.
Can someone be on several lists?+
Yes, as many as you like. They’re still one contact.
Do segments slow down as my audience grows?+
Counts are worked out when you look at them, so a very large account sees a moment’s delay on the segments page rather than anything being stale. The trade is deliberate: a cached count that’s wrong is worse than a fresh one that takes a second.