> ## Documentation Index
> Fetch the complete documentation index at: https://docs.virtuous.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Update a Contact Reference

> Updates the external referenceId and, optionally, the associated contactIndividualId. The contact and referenceSource cannot be changed. Omit contactIndividualId or set it to null to clear the association.



## API Specification

The full API specification for this endpoint is available in the [documentation index](https://docs.virtuous.org/llms.txt).


## Related topics

- [Update a Contact](/crm/workflows/update-a-contact.md)
- [Update a Contact Note](/api-reference/contacts-and-individuals/update-a-contact-note.md)
- [Update a Contact Address](/api-reference/contacts-and-individuals/update-a-contact-address.md)
- [Update a Contact Method](/api-reference/contacts-and-individuals/update-a-contact-method.md)