# Type Alias: ContactId

> **ContactId**: `Brand`\<\`$\{AccountNumber\}@$\{ChatServer\}\`, `"ContactId"`\>

A contact id ends with `@c.us` and only contains the number of the contact. For example, if the country code of a contact is `44` and their number is `7123456789` then the contact id would be `447123456789@c.us`

Example:

`"447123456789@c.us"`
