How to build retention for two-sided marketplaces?

For two-sided marketplaces (where there are two user groups, such as buyers and sellers), building retention requires considering the behavior of both sides and their interactions.

Main steps:

1. Identify key events for each side — for example, for buyers, it could be making a purchase; for sellers, listing a product or receiving an order.

2. Segment users by roles — analyze retention separately for buyers and sellers.

3. Analyze interactions between the sides — for example, buyer retention may depend on seller activity and vice versa.

4. Use cohort analysis — track how groups of users who joined during a specific period continue to use the marketplace.

5. Visualize retention considering both sides — create matrices or charts showing how retention of one side affects the other.

Example: you can build retention metrics for buyers who made their first purchase from a specific seller and see whether they return to that seller or to the marketplace in general.

Thus, it is important to consider the interdependence of the two groups and build metrics that reflect their interaction, not just individual activity.