Ontario, CA Animal Ordinances: Pet Limits (2026)

Under Ontario Development Code Section 5.03.410.C.1.a(1), the keeping of 4 or fewer household pets is permitted by right within all residential and mixed-use zoning districts, and within the AG and MHP zoning districts, in conjunction with a single-family or multiple-family dwelling. Keeping more pets is tied to lot size: Table 5.03-6 (Maximum Animal Keeping Densities as an Accessory Use) sets the maximum density for Household Pets at one animal for each 6,000 square feet of net lot area, and a portion of the lot used to qualify one animal type cannot be reused to qualify another. The Land Use Matrix (Table 5.01-1) confirms that '4 or fewer pets' is a permitted use across the residential districts. Special limits apply to certain animals kept as pets: only one potbellied pig is allowed per lot (Sec. 5.03.410.C.1.b(3)(c)), and exotic pets require a Conditional Use Permit (Sec. 5.03.410.C.1.b(2)). All dogs over four months of age must also be licensed with the City, with discounted rates for spayed/neutered animals.