How to handle a roommate who never cleans
Describe the specific tasks that are not happening and how they affect the home. Ask whether the current system is unclear, unrealistic, or simply being ignored. Then set a written rotation or choose fixed ownership by task.
Make standards concrete: bathroom Sunday, dishes within 24 hours, trash Tuesday night. Do not clean everything silently and hope the person notices.
If the agreement is repeatedly ignored, document it and discuss consequences allowed by the household agreement or lease.