Legal Question in Real Estate Law in California

As a roommate, you might might be either a subtenant, (co)tenant or a lodger (to use the legal terms). Tenants of either kind have much more substantial rights than lodgers. You would be a lodger and subject to being asked to leave on short notice, rather than a tenant, based on a variety of facts and circumstances.

You are likely to be a lodger rather than a tenant if some of the following are true:

1. You have a bedroom, but share the rest of the residence with another, including the kitchen and living room;

2. You are not included on the lease from the owner or landlord;

3. The intention of the parties at the time you moved in was that the other person would be in more or less control of the property, including paying the landlord, the utilities, taking care of maintenance, etc.

4. Your written agreement with the other occupant does not refer to you as a tenant or subtenant.

Tenants tend to have distinct and complete dwelling units, whereas lodgers tend to have a bedroom but share the rest of the facilities with the owner or a longer-term tenant who has a written lease with the owner (and which doesn't mention the other occupant).