Short answer

A Rollup property calculates the min, max, count, sum, average, earliest date or latest date of a property across associated records. Create a property, set Field type to Rollup, pick the rollup type, then the associated record type and property. Count counts associated records that have a value for the chosen property. Rollups need Professional or Enterprise.

1. The field type

Field type dropdown with Rollup highlighted — Rollup (1).

2. The settings

In my demo portal, picking Rollup shows Rollup type (Min by default), Number format, and the associated record type. Nothing was saved.

Rollup property settings with Rollup type Min, Number format and Choose the associated record type — Field type (1), rollup type (2), and associated record type (3).

3. Examples

Company: count of open tickets, latest activity on renewal deals.
Contact: number of associated deals in a pipeline.
Combine with a calculation property for things like time since a rolled-up date. See calculation properties.

Sources

HubSpot Knowledge Base: Create calculation and rollup properties
HubSpot Knowledge Base: Understand property field types in HubSpot

Rollup properties: count, sum or find the latest value across associated records

Short answer

1. The field type

2. The settings

3. Examples

Sources

New field notes by email

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