Yes, some residential lease agreements in Ohio need to be notarized. If the lease duration is longer than three (3) years, the lease has to be notarized in order to be valid.
If leases of three years or longer are not notarized, the 3-year lease is no longer valid. The tenancy is instead considered a month-to-month lease.
Leases for a duration of less than three years do not have to be notarized, and they are valid as long as they are signed. The tenant and landlord can agree to have a lease of any duration notarized if they wish, but it is not required for durations shorter than three years.
The information for this answer was found on our Ohio Residential Lease Agreement answers.