Segments let you divide your audience into groups based on specific conditions, so you can send the right content to the right people. You can access segments from Audience → Segments.
The number of segments available depends on your plan.
Dynamic vs. Static segments
When creating a segment, you choose between two types:
- Dynamic: Membership updates automatically every night based on conditions. As subscribers meet or stop meeting the criteria, they’re added or removed.
- Static: Membership is frozen at the moment of creation. Subscribers won’t be added or removed automatically even if their behavior changes.
Use dynamic segments for ongoing targeting (e.g. “engaged readers”) and static segments for one-time sends to a fixed group.
Creating a segment
- Go to Audience → Segments.
- Click New Segment.
- Enter a name and optionally a description.
- Choose Dynamic or Static.
- Add one or more filter conditions.
- Save the segment.
LetterBucket will process the segment in the background. Once ready, you’ll see the subscriber count and metrics.
Filter conditions
Each condition is made up of a field, an operator, and a value. Multiple conditions are combined with AND logic — a subscriber must match all of them to be included.
Available fields:
| Field | Description |
|---|
| Total Opens | Number of emails the subscriber has opened |
| Total Clicks | Number of links the subscriber has clicked |
| Subscribed Date | When they joined your list |
| Unsubscribed | Whether they’ve unsubscribed |
| Operator | Use case |
|---|
| IS / IS NOT | Exact match or exclusion |
| CONTAINS / DOES NOT CONTAIN | Partial string match |
| BEGINS WITH / ENDS WITH | Prefix or suffix match |
| EXISTS / DOES NOT EXIST | Field has any value or none |
| BEFORE / AFTER / BETWEEN | Date comparisons |
Segment metrics
Each segment shows:
- Total subscribers in the segment
- Open rate of that group
- Click rate of that group
- Unsubscribe rate of that group
These metrics help you understand the quality of each group before targeting them.
Using a segment
When sending or scheduling an email, open the Audience dropdown in the Delivery Settings step and select the segment. The summary box will show you how many subscribers will receive it.
Start by sending to your most engaged segment. Higher open and click rates from your first sends help build your sender reputation before you reach the rest of your list.
Exporting a segment
You can export the subscriber list of any segment as a CSV file. The export includes email address, name, and subscription status.
Deleting a segment does not delete the subscribers inside it. Only the grouping is removed.
