> ## 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.

# Set Primary Donor Phone Number

> Makes a phone number the donor's primary one, clearing `isPrimary` on the number that held it before.

<Info>This is the number used when the donor's record shows a single `phone`.</Info>


## API Specification

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