If one of your roommates who has signed the lease wants to leave before the term is up, you’re technically required to notify your landlord and either cover the rent yourself or find a new tenant to fit the terms of the lease.

But unless your building is pretty strict, you can probably just line up another tenant without having to notify your landlord at all. Most landlords won’t object, as long as the rent keeps coming in. Of course, until you find another roommate, you’ll be responsible for your ex-roommate’s share. And if anything goes wrong with the apartment and your new roommate isn’t on the lease, chances are you’ll have to take full responsibility.

If you can’t afford to keep your place until you find a new roommate, or if you just want to get out of a bad situation, you might want to move out as well. In that case, let your landlord know in writing, and be as flexible as you can in helping to find new tenants. The sooner you do, the sooner you’ll stop being liable for rent, and the less likely your landlord will be to take money out of your security deposit or threaten you with legal action for nonpayment.