---
title: "Update an existing custom event property"
method: PATCH
path: "/events/2026-03/event-definitions/{eventName}/property/{propertyName}"
tags: ["Basic"]
---

# Update an existing custom event property

`PATCH /events/2026-03/event-definitions/{eventName}/property/{propertyName}`

Update an existing property in a custom event definition.

## Path parameters

- `eventName` string, required
- `propertyName` string, required

## Request body

- EventsDefinitionsExternalBehavioralEventPropertyDefinitionPatch
  - `description` string — A description of the property that will be shown as help text in HubSpot.
  - `label` string — Human readable label for the property. Used in HubSpot UI
  - `options` OptionInput[] — A list of available options for the property if it is an enumeration. NOTE: This field is only applicable for enumerated properties.
    - `description` string
    - `displayOrder` integer, required
    - `hidden` boolean, required
    - `label` string, required
    - `value` string, required

## Response `201`

successful operation

- Property — A HubSpot property
  - `archived` boolean — Whether or not the property is archived.
  - `archivedAt` string, date-time — When the property was archived.
  - `calculated` boolean — For default properties, true indicates that the property is calculated by a HubSpot process. It has no effect for custom properties.
  - `calculationFormula` string — The formula used for calculated properties.
  - `createdAt` string, date-time — When the property was created
  - `createdUserId` string — The internal ID of the user who created the property in HubSpot. This field may not exist if the property was created outside of HubSpot.
  - `currencyPropertyName` string — The name of the related currency property.
  - `dataSensitivity` 'highly_sensitive' | 'non_sensitive' | 'sensitive' — Indicates the sensitivity level of the property, such as "non_sensitive", "sensitive", or "highly_sensitive".
  - `dateDisplayHint` 'absolute' | 'absolute_with_relative' | 'time_since' | 'time_until' — Controls how date properties are displayed in the HubSpot UI, with options such as 'absolute', 'absolute_with_relative', 'time_since', and 'time_until'.
  - `description` string, required — A description of the property that will be shown as help text in HubSpot.
  - `displayOrder` integer — The order that this property should be displayed in the HubSpot UI relative to other properties for this object type. Properties are displayed in order starting with the lowest positive integer value. A value of -1 will cause the property to be displayed **after** any positive values.
  - `externalOptions` boolean — For default properties, true indicates that the options are stored externally to the property settings.
  - `fieldType` string, required — Controls how the property appears in HubSpot.
  - `formField` boolean — Whether or not the property can be used in a HubSpot form.
  - `groupName` string, required — The name of the property group the property belongs to.
  - `hasUniqueValue` boolean — Whether or not the property's value must be unique. Once set, this can't be changed.
  - `hidden` boolean — Hidden options won't be shown in HubSpot.
  - `hubspotDefined` boolean — This will be true for default object properties built into HubSpot.
  - `label` string, required — A human-readable property label that will be shown in HubSpot.
  - `modificationMetadata` PropertyModificationMetadata
    - `archivable` boolean, required
    - `readOnlyDefinition` boolean, required
    - `readOnlyOptions` boolean
    - `readOnlyValue` boolean, required
  - `name` string, required — The internal property name, which must be used when referencing the property via the API.
  - `numberDisplayHint` 'currency' | 'duration' | 'formatted' | 'percentage' | 'probability' | 'unformatted' — Hint for how a number property is displayed and validated in HubSpot's UI. Can be: "unformatted", "formatted", "currency", "percentage", "duration", or "probability".
  - `options` Option[], required — A list of valid options for the property. This field is required for enumerated properties, but will be empty for other property types.
    - `description` string — A description of the option.
    - `displayOrder` integer — Options are displayed in order starting with the lowest positive integer value. Values of -1 will cause the option to be displayed after any positive values.
    - `hidden` boolean, required — Hidden options will not be displayed in HubSpot.
    - `label` string, required — A human-readable option label that will be shown in HubSpot.
    - `value` string, required — The internal value of the option, which must be used when setting the property value through the API.
  - `referencedObjectType` string — If this property is related to other object(s), they'll be listed here.
  - `sensitiveDataCategories` string[] — When sensitiveData is true, lists the type of sensitive data contained in the property (e.g., "HIPAA").
  - `showCurrencySymbol` boolean — Whether the property will display the currency symbol set in the account settings.
  - `type` string, required — The property data type.
  - `updatedAt` string, date-time — When the object type was last updated.
  - `updatedUserId` string — The internal user ID of the user who updated the property in HubSpot. This field may not exist if the property was updated outside of HubSpot.

## Other responses

- `default` — An error occurred.

---

[API](https://skmtc.net/hubspot/apis/hubspot-api-specification.md) · [All operations](https://skmtc.net/hubspot/apis/hubspot-api-specification/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/hubspot/hubspot-api-specification/versions/f9c7181056c5/schema)