Yes, you can typically use the bathroom while your septic tank is being pumped. The process of septic tank pumping involves removing the accumulated solids and liquids from the tank, which is typically done through an access point called the septic tank cleanout or access port. However, it's a good idea to communicate with the septic tank pumping service provider and inform them about your intention to use the bathroom. They may provide guidance on any precautions or temporary measures to ensure the smooth and safe operation of the pumping process.