A segment is a rule. At launch, it becomes an audience.
Define who a campaign should reach in terms of what they have done — opened or clicked in the last ninety days, gone quiet for five campaigns, never complained. When the campaign launches, the platform resolves the rule into a fixed audience, so the audience and the report describe the same people. Send to the engaged first. Re-engage the quiet. Stop mailing the ones who will never open.
A segment that keeps moving is a report you cannot read.
Segments on most platforms are live queries. That sounds like a feature until you try to explain a report. The campaign went to “engaged subscribers” — but the definition kept changing while the campaign sent, so the audience count on the report does not match the one you launched with, and the open rate is calculated against a moving denominator. Nobody can say who the campaign actually reached.
SendTo separates the two ideas. A segment is a rule: a description of who should receive a campaign. At launch, the rule is resolved once into a fixed audience, and that audience is what the campaign sends to and what the report measures. The rule stays live for the next campaign. The audience stays fixed for this one.
This is also what makes engagement-first sending safe — and engagement-first sending is the single fastest way to build a new domain’s reputation. With a rule, that is one segment, reused forever.
Engagement, as a rule
Build a segment from what subscribers have done: opened or clicked within a window, quiet for a number of campaigns, joined recently, never complained. Combine conditions. The platform shows how many currently match, and the campaign builder shows the reachable count — matches that are verified and not suppressed — before you launch.
- Engagement conditions over windows and campaign counts
- Live match count while you build
- Reachable count in the campaign builder
● Automated 12.1%
Scanners never count as customers.
| Variation | Subject line | Human opens | Clicks |
|---|---|---|---|
| A · winner | Your six-month check-up is due, {first name} | 33.2% | 7.4% |
| B | Six months already? Let’s keep that smile on track | 29.6% | 6.2% |
Frozen at launch
When a campaign launches against a segment, the platform takes a snapshot: the rule is resolved, the audience is fixed, and every number on the report is measured against it. Subscribers who would match tomorrow are in tomorrow’s campaign. The report is honest because the denominator does not move.
- Snapshot taken at launch
- Report measured against the snapshot
- Rule stays live for the next campaign
The three segments partners use most
Engaged last 90 days to launch a new client or a new domain. Quiet for five campaigns for a re-engagement send with a lighter touch. Never engaged to stop mailing — the addresses that drag reputation down and never open. Each is one rule, built once, reused on every campaign.
- Engaged-first launches for new domains
- Re-engagement sends for the quiet
- Sunset rules for the never-engaged
Send to the right people, and prove it on the report.
Better numbers, faster
Engaged-first sending builds a new domain’s reputation quickly and produces open rates a client is proud to see in month one.
Reports that add up
The audience count on the report is the audience the campaign went to. The client never reconciles two numbers.
Less mail to people who never wanted it
Sunset rules protect the domain — and, quietly, the client’s brand.
Engaged-90 is the first campaign every new client gets from us now. It is the fastest way I know to make a domain look good.
Questions
What can a segment be based on?
Engagement over time — opens and clicks within a window, engagement across a number of campaigns, join date, complaint history — combined as you need.
Does the segment update after launch?
The rule does. The campaign’s audience does not. The report measures the audience the campaign actually went to.
Are unverified or suppressed addresses excluded?
Yes. The reachable count is matches that are verified and not suppressed. Nothing else is sent to.
Do segments count human opens or all opens?
Engagement rules use classified activity, so automated opens from security scanners never make a subscriber look engaged when they are not.
Send to the right people. Prove it on the report.
Build a rule once. Launch against it forever.
No contract · Cancel any time · Explore everything before you pay