You can change your username in the Venmo app by following these steps:
- Go to the Me tab
- Tap the Settings gear in the top right
- Tap Account, then Profile
- In the username field, update your username
- Save your changes
Your Venmo username must be between 5 and 30 characters (no special characters other than - and _ ).
You can update your username on the web, or select Settings then Profile from the left side of your screen to view or edit your username.