Modesto, CA Short-Term Rentals: Registration Rules (2026)

Because the County has no dedicated short-term-rental program, registration happens through two existing County systems rather than an STR portal. First, a business operated out of an unincorporated-area location generally needs a County business license; a home-based use is licensed as a Home Occupation, and the Treasurer-Tax Collector issues these licenses and renewals for locations outside city limits. Second, anyone furnishing lodging to transients for compensation must register with the Treasurer-Tax Collector's Business Services Division for the Transient Occupancy Tax. Registration produces a TOT Certificate number, which is entered on the "Quarterly Report of Transient Occupancy Tax as Required by Ordinance 4.04" form. That form is the recurring filing: a return must be filed every quarter even if no tax is due, with periods ending September 30, December 31, March 31 and June 30, and each report due the last day of the following month. Operators must keep all records substantiating the return for not less than three years from the date of payment, and any change of address or ownership must be reported immediately to the Treasurer-Tax Collector. There is no statewide California STR registration, so these County registrations are the operative steps.