You probably think the county assessor is the person you should blame when your tax bill lands in the mailbox and makes your stomach drop. Most people do. Honestly, it’s one of the biggest misconceptions in local government. If you live in Maricopa County, the guy currently holding that hot seat is Eddie Cook. He’s been the Eddie Cook County Assessor since he was appointed in early 2020, and he’s been winning elections to keep the job ever since.
But here’s the thing: Eddie Cook doesn’t actually set your tax rates.
He doesn’t collect the money, either. That’s the Treasurer’s job. Basically, Cook and his team are the data people. They’re the ones looking at over 1.8 million parcels of land across the valley—from the sprawling mansions in Paradise Valley to the retirement condos in Sun City—to figure out what everything is worth. It’s a massive, technical, and often thankless grind of math and market analysis.
Who Is Eddie Cook, Anyway?
Before he was the Eddie Cook County Assessor, he wasn't a career politician in the traditional sense. He spent over 30 years in the high-tech industry. We're talking 20 years in leadership at a company dealing with cloud-based data for Fortune 100 giants. He also served on the Gilbert Town Council for a decade.
When the Maricopa County Board of Supervisors needed someone to clean up the office in 2020 after the previous assessor, Paul Petersen, resigned amid a massive legal scandal, they wanted a "business guy." Cook was that guy. He brought this "One Team" philosophy from the corporate world, which sounds like typical buzzword fluff, but in a government office that was previously in total disarray, it actually meant something.
Born in Okinawa, Japan, and married to his high school sweetheart, Cook is kind of a tech geek at heart. He’s a certified glider pilot and does astrophotography in his spare time. That detail matters because it explains his obsession with the "MARS" project—the Maricopa Assessment Replacement System. It’s a huge IT overhaul designed to drag the county’s property data into the 21st century.
The Cook County vs. Maricopa Confusion
There is a hilarious bit of naming irony here. People often search for "Eddie Cook County Assessor" thinking he runs the office in Cook County, Illinois (Chicago). He doesn't. That’s Fritz Kaegi.
Funny enough, the two actually work together. In 2025, Eddie Cook and Fritz Kaegi co-sponsored a resolution through the National Association of Counties (NACo) to get better access to federal housing data. It’s a weird "Assessor Multiverse" moment where the guy named Cook and the guy from Cook County teamed up to lobby the feds for more transparency in property characteristics.
What Does the Assessor Actually Do for You?
If you're a homeowner, your interaction with Cook's office usually starts and ends with the "Notice of Value" (NOV). In Maricopa County, these are typically mailed out in February.
- Valuation: They determine the "Full Cash Value" (FCV) based on market conditions from about 18 months prior.
- Classification: They decide if your property is residential, commercial, or agricultural. This is huge because different classes are taxed at different percentages.
- Exemptions: This is where the office actually saves people money. They handle the Senior Valuation Protection (the "Senior Freeze") and exemptions for widows, widowers, and people with disabilities.
Cook has been pretty vocal about legislative wins lately. Take SB 1122, for example. Before this passed, the valuation cap for personal exemptions was tied to GDP. Cook argued—rightly so—that GDP has nothing to do with the housing market. Now, it’s tied to the Federal House Price Index, which keeps more vulnerable people from being priced out of their tax breaks just because their home value went up on paper.
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The 2026 Valuation Cycle: What to Watch
As we head through 2026, the office is operating under a "Digital First" strategy. If you think your property was valued too high, you don't have to mail in a stack of papers anymore. You can do the whole appeal online.
Important Date: The deadline to file an appeal for the 2026 Notice of Value is usually in April. If you missed it for this year, you’re basically stuck with the value until the next cycle unless there's a major error in the physical description of your house.
Under Cook, the office has actually stayed under budget while being named one of Arizona’s "Top Workplaces." That’s rare for a government agency. Most people only care about the Assessor when their valuation spikes, but behind the scenes, Cook has been pushing for things like SB 1549 to standardize how conservation easements are valued, ensuring that "fair and equitable" isn't just a slogan on the website.
How to Handle Your Property Value Right Now
If you're looking at your latest notice and wondering why the Eddie Cook County Assessor office thinks your 1970s ranch house is worth a million dollars, here is the move.
First, check your "Limited Property Value" (LPV). In Arizona, thanks to Proposition 117, your LPV—the number actually used to calculate most of your taxes—can’t grow by more than 5% per year. Even if the market goes crazy and your Full Cash Value jumps 30%, your taxable value is capped.
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Second, look for the "Notice of Change." If you did a renovation or added a casita, the office will send this out between September and October. This is your chance to make sure they didn't over-estimate the value of that new square footage.
Next Steps for Homeowners:
- Log onto the Maricopa County Assessor’s portal and use the "Parcel Viewer" to compare your valuation with your neighbors.
- Check your eligibility for the Senior Valuation Protection if you are 65 or older and meet the income requirements.
- If you're planning an appeal, start gathering "comps" (comparable sales) from your specific neighborhood from the middle of the previous year, as the Assessor’s office is legally required to look at a specific window of time, not just what's happening today.