Two 1912 Craftsman bungalows sit three doors apart in the blocks around Riverside's Raincross District, both with the same square footage, the same covered porch, the same assessed value on paper. One owner pays a property tax bill that's roughly half the other's. The house itself didn't change. What changed is a piece of paper filed with the county years ago, and that paper is worth more to a buyer than almost anything else in the listing.
That paper is a Mills Act contract, and the gap it creates is the thing most buyers shopping Riverside's historic core get wrong. They assume "old house" and "tax break" are the same sentence. They aren't.
Age doesn't get you the discount. A signature does.
The Mills Act is a 1972 state law that lets cities enter into contracts with owners of qualified historic properties, trading a lower property tax bill for a commitment to maintain and restore the home. Riverside runs its own program under this law, and the city's historic preservation office is clear that the tax relief only applies to properties with a recorded contract, not to every home that happens to qualify.
Qualifying is the easy part. A property has to carry one of three designations: individually listed as a City Landmark, listed as a Structure of Merit, or recognized as a contributor to a designated Historic District or Neighborhood Conservation Area. Riverside has plenty of these, from the homes clustered near Mt. Rubidoux, which has its own dedicated set of historic district design guidelines, to the bungalow-and-Craftsman blocks around downtown and the Raincross District.
But qualifying and having a contract are two different states. A home can be a fully eligible Structure of Merit and still be paying full freight on property taxes, simply because no one ever filed the paperwork. That's the detail that doesn't show up in a listing photo, and it's the reason two nearly identical houses on the same street can carry wildly different carrying costs.
What the discount is actually worth
When a Mills Act contract is in place, the county assessor stops using the standard market approach to value the property and instead uses an income approach, essentially valuing the home as if it were a rental and applying a set capitalization rate. In most cases, that number comes in well below the market value, and the lower of the two gets enrolled for tax purposes.
The city's own figures put the resulting savings at generally 20 to 60 percent of the annual property tax bill, depending on the individual property's attributes and current valuation. That's not a rounding error. On a home assessed anywhere near the $639,900 median that homes in the neighborhoods surrounding downtown Riverside were fetching as of August 2026, a 40 percent swing in the tax bill is real money every single year, for as long as the contract stays active.
And contracts stay active a long time. The minimum term is ten years, but the contract renews automatically each year on its anniversary, which means it functions as a rolling ten-year commitment rather than something that quietly expires. If neither the owner nor the city files a notice of non-renewal, the clock effectively never runs out.
The part that transfers with the house, and the part that doesn't
Here's the mechanism buyers need to understand before they fall in love with a listing that mentions Mills Act eligibility: the contract runs with the land, not with the person who signed it. When the house sells, the contract and its tax treatment pass automatically to the new owner. You don't apply for someone else's discount. You inherit it.
That sounds like a pure win, and often it is. But the contract also carries obligations that transfer along with the benefit:
- The city can inspect the interior and exterior before approving a new contract and at minimum every five years afterward, to confirm the owner is holding up their end.
- Exterior changes visible from the street go through a Certificate of Appropriateness review, so a buyer who wants to swap out original windows or reconfigure the front elevation may find that harder than it would be on a non-contracted historic home.
- If the city determines the owner has breached the agreement or let the property deteriorate below the standard for a qualified historic property, it can cancel the contract, which brings the tax bill back to standard levels and can come with financial penalties.
None of this makes Mills Act homes a bad buy. It means the tax savings and the preservation obligations are a package deal, and a buyer evaluating a historic Riverside property should ask to see the actual recorded contract, not just take a listing's word that the home is "Mills Act eligible." Eligible and contracted are not the same word, and only one of them changes your tax bill.
Why you can't just apply your way into it
If a home you love doesn't already have a contract, you can apply for one after closing, but the timeline and the odds are worth knowing up front. Riverside only accepts Mills Act applications between January 1 and May 31 each year, so if you close in July, you're waiting until the following January just to submit paperwork.
Even then, approval isn't automatic. The city currently allocates an average of fifteen and a maximum of twenty new contracts per year, split roughly thirteen for residential properties and two for commercial. If more qualified applications come in than there are slots available, the properties are selected at random. A homeowner can do everything right, hold a genuinely eligible Structure of Merit, and still not get one of that year's contracts.
The financial barrier to applying has also changed recently in a way worth knowing. In March 2024, the Riverside City Council voted to cut the combined application and contract initiation fees from $3,678 down to $975 for that year's cycle. The current application packet lists the fee as $126 for the application plus $957 to initiate the contract, a total that's still a fraction of what it cost before 2024. Lowering that barrier likely means more owners are applying now than in prior years, which makes the cap on total contracts an even tighter bottleneck than it used to be.
What this means if you're comparing Riverside neighborhoods
For a buyer weighing a move into one of Riverside's older, character-rich pockets against a newer build elsewhere in the Inland Empire, the Mills Act changes the math in a way that a median price alone won't show you. Two homes can carry the same sticker price and produce very different total ownership costs, and the only way to know which one you're looking at is to ask directly whether a Mills Act contract is recorded on the title, and to have that confirmed through the county rather than assumed from a listing description.
It also means a home without a contract isn't automatically the worse deal. If you're planning to stay long enough to see an application through a competitive cycle, and you're comfortable with the maintenance standards and periodic inspections that come with the territory, buying an eligible-but-uncontracted property and applying yourself is a real option. You're just signing up for a process with a real chance of not getting picked in any given year.
If you're comparing homes in Riverside's historic districts, this is exactly the kind of detail worth running down before you write an offer, not after. A pre-approval and a comparable sale tell you what a house is worth. Only the county record tells you what it will actually cost to keep.
A few questions worth asking before you write an offer
Does a Mills Act contract automatically transfer when I buy the house? Yes. The contract is recorded against the property, not the person, so a new owner takes on both the tax benefit and the maintenance obligations the day escrow closes.
Can I remove or modify a Mills Act contract I don't want? Owners can file a notice of non-renewal, but the contract doesn't disappear immediately. It continues on a declining schedule for the remainder of its current term before it fully lapses, so it's not something you can undo the week after closing.
If a listing says a home is "Mills Act eligible," does that mean I'll get the tax savings? Not automatically. Eligibility means the property qualifies for a contract, not that one exists. You'd need to apply during the city's January through May window and hope for one of the limited slots awarded that year.
If you're weighing a historic Riverside property against something newer, or you want help confirming whether a specific address actually carries a recorded contract before you make an offer, Christine Smith has spent years working these blocks and knows where to look. Let's get you the keys. Book a free consultation and let's figure out what a house like this will really cost you to own.
