Please follow these instructions to activate a new retail purchase on Steam:
- Launch the Steam client software and log into your Steam account.
- Click the Games Menu.
- Choose Activate a Product on Steam…
- Follow the onscreen instructions to complete the process.
- Borderlands 2 base game
- Borderlands: The Pre-Sequel base game
- All available downloadable content for Borderlands 2 and Borderlands: The Pre-Sequel as of December 31st, 2017