A month-to-month tenancy is a periodic tenancy or lease in which the tenant is given possession of the leased premises with no specific expiration date and agrees to pay the landlord on a monthly basis. A month-to-month tenancy often requires the tenant or the landlord to give the other party 30 days written notice of termination of the lease.

Both residential leases and commercial leases may be month-to-month tenancies. If a residential or commercial tenant remains in the leased premises and continues to pay rent following the expiration of a lease for a longer term, there may be a new month-to-month tenancy created and recognized by law.

In Pennsylvania, a month-to-month tenancy is recognized as a form of periodic tenancy where the tenant occupies the property with no definite lease end date and pays rent monthly. This arrangement can be established either through an explicit agreement or by implication, such as when a tenant remains in the property after the expiration of a fixed-term lease and continues to pay rent, and the landlord accepts it. For termination of a month-to-month tenancy, Pennsylvania law generally requires either the tenant or the landlord to provide the other party with a 15-day notice if the tenancy has lasted for less than one year, and a 30-day notice if the tenancy has lasted for one year or more. This notice must be in writing. These requirements apply to both residential and commercial month-to-month tenancies. It's important to note that local ordinances may impose additional requirements, so it's advisable to consult with an attorney or review local laws for specific regulations that may apply.