Does a Florida rent increase notice need to be in writing?

Yes. Florida requires a written notice for any rent increase on a month-to-month tenancy or at the end of a fixed term. Florida has no statewide advance notice for rent increases. Fla. Stat. 83.57 (post-HB 1417, effective July 1, 2023) requires 30 days notice to terminate a month-to-month tenancy, which landlords use as the default for rent changes. No state rent cap. An oral notice is generally not enforceable; the tenant can refuse to pay the increased amount and the landlord cannot evict for nonpayment of an unwritten increase. The written notice should state the current rent, the new rent, the effective date (which must be after the statutory notice period), and the landlord's signature. Delivery follows the same service rules as other landlord notices: personal delivery, substituted service, or posting plus mailing.

Source: Fla. Stat. 83.57 (30-day month-to-month termination default, post-HB 1417)