But a higher appraisal doesn’t always mean it’s accurate. If your home’s condition, size, or features differ from HCAD’s assumptions, you may have grounds to appeal and reduce your property taxes.
If you’re a homeowner in Harris County, Texas, your Harris County tax appraisal — as determined by the Harris County Appraisal District (HCAD) — can be one of the biggest surprises each spring. There are often inaccuracies in appraisals that result in higher and unfair tax bills.
In fact, over 866,000 Harris County residential properties (78%) didn't protest their property taxes in 2025.
In this guide, you’ll discover exactly how HCAD estimates your property’s value, why your number may have jumped, and step-by-step how to protest to ensure you're not one of the home or property owners overpaying on property taxes.
Summary
What is it?
A Harris County tax appraisal is HCAD’s estimate of your property’s market value as of January 1. HCAD sets the value, while cities, counties, school districts, and other taxing entities set tax rates.
What to do?
Open your notice, verify the details, and compare values to similar recent sales. If the value is high or the data is wrong, gather proof and file a protest. Even a modest reduction can lower your total bill across all taxing entities. For more information, check out our guides about market vs. assessed value
When to act?
The main protest deadline is May 15 or 30 days after HCAD mails your notice, whichever is later. Don’t wait. File early through HCAD’s iFile Protest portal.
How HCAD Determines Your Harris County Tax Appraisal Value
HCAD uses three primary methods to estimate your taxable market value as of January 1: You can confirm details and values in HCAD’s Property Search.
Sales comparison approach: Looks at recent sales of similar properties, adjusted for features like size, age, condition, and location. It’s the most common appraisal method for residential homes.
Cost approach: Estimates what it would cost to replace the structure, minus depreciation, plus land value. It uses cost data from a national supplier of construction cost information
The income approach: Values the property based on income and expenses. HCAD is more likely to use this approach for apartments, retail, office buildings, warehouses, and other properties people purchase to produce income.
Market Value vs. Taxable (Assessed) Value: What’s the Difference?
After estimating your market value, HCAD applies exemptions and caps to calculate your assessed value. Market value and assessed value aren’t the same thing.
Term | What it means | Why it matters |
|---|---|---|
Market value | What your home could sell for on Jan 1 according to HCAD’s data | It’s the starting point for your appraisal |
Taxable/assessed value | The value HCAD uses after applying homestead caps and exemptions | Your tax bill is based on this figure, not the raw market value |
According to Texas law, once you have a homestead exemption the assessed value cannot increase by more than 10% a year, plus the value of any new improvements. Once the exemption is in place, this cap protects you from sudden jumps in your tax bill, even when home prices rise sharply.
Why Did My Harris County Appraisal Jump?
If your 2025 appraisal feels unexpectedly high, market conditions are probably the main reason.
In recent years, high demand, limited housing inventory, and steady neighborhood upgrades across Houston have pushed comparable sales higher, especially in fast-growing school districts like Houston ISD, Cypress-Fairbanks ISD, and Katy ISD. HCAD’s models track those sales closely, so small market changes can snowball into large increases in your property’s appraised value.
Other factors that can trigger a large, immediate value change include:
New construction or major remodels and additions completed before January 1
Recent ownership transfer or new purchase near market value.
HCAD reappraisal cycles targeting certain neighborhoods or property values. According to the HCAD, homes above $450,000 had value increases of 7 to 12% in 2024.
Altogether, 57% of homes in the county increased in value, 31% decreased, and 12% remained unchanged.
The homestead exemption was removed, for example, because you moved and rented out the home.
How Property Appraisals Affect Your Tax Bill
Your property tax bill follows a simple formula: Taxable Value × Total Tax Rate = Property Tax Bill.
HCAD first establishes your property’s market value. It then adjusts that value based on applicable caps and exemptions — like those for homesteads, seniors over 65, or disabled homeowners — to determine your taxable value.
From there, each taxing entity sets its own rate. That includes Harris County, the Harris County Flood Control District, the Harris Health System/Hospital District, your local school district (like Houston ISD or Cy-Fair ISD), and, depending on where you live, your city and community college district.
Your total property tax bill is the sum of all these rates applied to your taxable value.
Even if tax rates go up, you should consider protesting your tax bill if it looks unrealistically high. A successful appeal lowers your taxable value, which in turn reduces the amount you pay to every taxing unit. Even a small reduction can translate into significant savings, especially if you own multiple properties or a higher-value home.
To see how local rates and trends are shifting, look at our overview of Harris County property taxes, and explore our guides on ways to reduce your property taxes.
How to Check Your Harris County Tax Appraisal Online (and Spot Errors)
You can check your Harris County tax appraisal online using HCAD’s tools:
Go to HCAD Property Search: Visit HCAD’s Property Search page and enter your address or account number.
Confirm the basics: Confirm the general property details, such as owner name, legal description, lot size, year built, and property type (SFR vs. condo). Any inaccuracies affect value.
Review the values and exemptions.
Look at the market value, appraised/taxable value, and exemptions (such as homestead, over-65, or disabled). If your homestead exemption is missing, apply directly through HCAD or use Ownwell to file a retroactive exemption.
Compare to similar sales: Use the “Range of Addresses” search on the HCAD website to find recent sales of similar homes in your area. Texas law also allows you to inspect and copy HCAD’s evidence if you request it in writing at least 14 days before your Appraisal Review Board (ARB) hearing.
Estimate your tax bill: After confirming your values, you can estimate your property taxes using Ownwell's Harris County property tax calculator. Ownwell’s guide on calculating your property tax in Texas.
What to Look For In Your Appraisal
Once you have your appraisal record, make sure it accurately reflects your property. Errors or outdated data can justify a protest and potentially lower your bill. Check for:
Square footage and measurements: Incorrect living area, garage versus living space, or lot size.
Condition and quality: Foundation issues, roof age, prior flood damage, deferred maintenance, or finishes older than the “average” HCAD model assumes.
Amenities and features: Missing or incorrect listings for pools, sheds, or upgrades.
Photos and notes: Out-of-date imagery or neighborhood assumptions that don’t match your home’s actual condition.
Comparable sales (comps): Properties used as comps that are newer, larger, or more renovated than yours.
How to Successfully Protest Your Harris County Tax Appraisal
If your appraisal seems too high, you can challenge it through a protest. Follow these steps to get started:
File your protest (fastest online): Use HCAD’s iFile Protest portal. However, you'll need the iFile number printed on your Notice of Appraised Value.
When filing, pick your protest reasons, such as “over market value” and/or “unequal appraisal.”
Alternatively, you can file manually using the Property Tax Notice of Protest Form, which you can
sign online, fill out by telephone, or submit in person at HCAD offices or any Harris County Tax Office.
Consider the iSettle offer: After filing, many homeowners receive an iSettle offer from HCAD. This online tool lets you review a new suggested value.
You can accept immediately and skip a hearing if it’s reasonable.
However, if it’s not, you can decline and continue your protest. To strengthen your case, gather stronger comparables (comps) or proof of your home’s condition.
Prepare for the ARB hearing. If you proceed, you’ll present your case to the ARB remotely or in person. The ARB is an independent panel that reviews your evidence and decides whether your appraisal should be adjusted. Bring well-organized, clear documentation, such as:
Date-stamped photos showing property defects or maintenance issues
Contractor estimates or engineer reports
Recent comparable sales adjusted for age, condition, and location
Income and expense records (for rental or commercial properties)
If you don't have the time or expertise to file a strong property tax protest, use an expert like Ownwell to help you through the process and give you a better chance at protesting successfully.
Mind the deadline (again):
Texas’s main protest deadline is May 15 or 30 days after the mailing of notice, whichever is later. We recommend filing as early as possible to avoid missing your window.
What to Bring | Why it Matters |
|---|---|
Closing statement or independent appraisal | Shows what the buyer paid or the current market value |
Photographs of defects | Demonstrates condition-based reduction |
Comps with adjustments | Shows your home is over-valued relative to peers |
Repair estimates | Quantifies needed fixes that HCAD may have assumed completed |
Take Control of Your Harris County Property Taxes
When you get your appraisal notice, please review it carefully, verify the details, and challenge any value that doesn’t reflect your property’s true condition or market reality. Even a small reduction can lower what you pay across every Harris County taxing entity.
Remember, the protest deadline is May 15 or 30 days after your notice was mailed, whichever is later. The earlier you act, the better your chance of building a strong case to secure savings.
If you don't have the time or expertise, start the appraisal process with Ownwell.
Enter your address to find out if your Harris County property is over-appraised, and we’ll handle the protest for you. Our Property Tax Consultants specialize in complex protests and work hard to maximize your chances of success.
