A Texas tax appraisal and a home’s market value measure two different things, which is why the number on your appraisal notice rarely matches what a buyer would pay. The county appraisal district sets a value as of January 1 using mass-appraisal models across thousands of homes, then legal protections like the 10 percent homestead cap and exemptions push your taxable number lower still. Market value, by contrast, is a theoretical current sale price that moves with interest rates, demand, and comparable sales. Understanding the Texas tax appraisal vs. market value gap tells you whether your notice is reasonable and what to do if it isn’t.
What Each Number Actually Measures
Texas law defines market value as the price a property would bring in a cash sale under normal conditions, assuming the seller has reasonable time to find a buyer, both sides know everything about the property’s uses and restrictions, and neither party is desperate enough to accept a bad deal.1State of Texas. Texas Tax Code 1.04 – Definitions The key word is “would.” Market value is a theoretical price, not a recorded sale, and it shifts with comparable sales, mortgage rates, buyer demand, and property-specific upgrades. A home’s market value in March can look different from its value in October.
Every county in Texas has a Central Appraisal District (CAD) responsible for identifying and valuing all taxable property within its boundaries. By law, the district must appraise your property at market value as of January 1 each year.2State of Texas. Texas Tax Code 23.01 – Appraisals Generally That date matters. If the market surges in the spring or crashes in the fall, the district’s number is still anchored to conditions as of New Year’s Day.
Unlike a lender’s appraiser, the CAD almost never walks through your house. These offices use mass appraisal techniques, running statistical models across thousands of properties at once and relying on neighborhood sales data, building permits, and aerial imagery. The result is a regulatory estimate, not a negotiated price. It’s good enough for tax purposes but often lags behind or overshoots what a buyer would actually pay on any given day. That mismatch is the core reason your tax notice and a Zillow estimate rarely agree.
Why the Homestead Cap Widens the Gap
The single biggest reason a tax appraisal trails market value is the homestead appraisal cap. If you have a filed homestead exemption on your primary residence, the appraisal district cannot increase your appraised value by more than 10 percent over the prior year, plus the value of any new improvements.3State of Texas. Texas Tax Code 23.23 – Limitation on Appraised Value of Residence Homestead The district still records what it believes the market value is, but your taxable appraised value is capped at that 10 percent ceiling.
Suppose your home’s market value jumps from $300,000 to $400,000 in a single year. The district cannot tax you on $400,000. Instead, your appraised value rises to at most $330,000, the prior year’s appraised value plus 10 percent. Over several years of strong appreciation, the spread between your capped appraised value and true market value can grow to six figures. This is working exactly as designed: the cap shields homeowners from enormous year-over-year tax increases.
Two catches apply. You must have qualified for the homestead exemption in both the current and the preceding year.4Texas Comptroller of Public Accounts. Valuing Property If you just purchased the home, the cap does not protect you for that first year; the district will set your value at full market value, and the 10 percent limit kicks in the following tax year. The cap also applies only to your primary residence. Investment properties, vacation homes, and commercial real estate get no such protection and are appraised at full market value every year.
Exemptions That Shrink the Taxable Number
The appraisal cap limits how fast your value can climb. Exemptions actually subtract dollars from the number that gets taxed. Every homeowner with a filed homestead exemption receives a $140,000 reduction for school district taxes.5State of Texas. Texas Tax Code 11.13 – Residence Homestead If your appraised value is $350,000, the school district only taxes you on $210,000.
Additional exemptions stack on top of that baseline. Homeowners who are 65 or older or disabled get an extra $60,000 off their school district taxable value.5State of Texas. Texas Tax Code 11.13 – Residence Homestead The Texas Constitution provides a $3,000 reduction for county purposes. Cities, counties, and special districts may adopt their own homestead exemption of up to 20 percent of appraised value, with a minimum floor of $5,000.
These exemptions do not change your home’s market value or even its appraised value. They reduce the assessed value that taxing units actually multiply by their tax rate. Filing for every exemption you qualify for is the simplest way to lower your bill without challenging the appraisal itself.
From Appraised Value to Your Tax Bill
The process flows in order. The appraisal district determines market value, applies the 10 percent cap (if you have a homestead exemption) to arrive at appraised value, then subtracts exemptions to produce your assessed or taxable value. Each taxing unit — school district, city, county, hospital district, water district — multiplies that assessed value by its own tax rate and sends a separate line item on your bill.
Say your capped appraised value is $330,000 and you have the standard $140,000 school district exemption. The school district taxes you on $190,000. If the school tax rate is $1.05 per $100 of value, your school taxes are $1,995. Repeat that calculation for every other taxing unit, usually four to seven of them, add them up, and that is your annual property tax bill. Every dollar the appraisal district adds to your value gets multiplied by every tax rate on your bill.
How to Protest Your Appraised Value
If your appraisal notice shows a number that doesn’t match reality, you have the right to challenge it. Most protests succeed on one of two arguments: the appraised value exceeds what the property would actually sell for, or the value is higher than comparable properties in the area. Gather evidence for at least one of those claims before you file.
Strong evidence includes closing documents from a recent purchase, especially if you paid less than the appraised value, an independent appraisal done for a mortgage, and photographs showing conditions the district may not know about, such as foundation damage, outdated interiors, flood history, or deferred maintenance. Sales data from comparable homes in your neighborhood also carries weight, particularly if those homes sold for less than your appraisal.
File a Notice of Protest using Form 50-132 (for counties with populations over 120,000) or Form 50-132-a (for smaller counties).6Texas Comptroller of Public Accounts. Property Owner’s Notice of Protest Both are available on the Comptroller’s website or through your local appraisal district’s online portal. On the form, check the box for incorrect appraised or market value, unequal appraisal compared to other properties, or both. That tells the Appraisal Review Board exactly what you’re contesting.
The deadline is May 15 or 30 days after the appraisal district mails your notice of appraised value, whichever comes later.7Texas Comptroller of Public Accounts. Appraisal Protests and Appeals The clock starts when the district mails the notice, not when it lands in your mailbox. Most districts accept electronic filing, though certified mail creates a paper trail if you want proof of timely submission.
What Happens After You File
Most districts schedule an informal meeting with a staff appraiser before the formal hearing. This is where the majority of protests get resolved. The appraiser reviews your evidence and, if it’s persuasive, offers a reduced value on the spot. You can accept or decline. Declining moves you to a formal hearing before the Appraisal Review Board, a panel of local citizens with the authority to adjust your value.7Texas Comptroller of Public Accounts. Appraisal Protests and Appeals
If the ARB rules against you and you still believe the value is wrong, you have two main options. You can request binding arbitration through the Comptroller’s office within 60 days of receiving the ARB’s order. The required deposit is $450 if the property is your homestead and valued at $500,000 or less, or $500 if it is your homestead valued above $500,000.8Texas Comptroller of Public Accounts. Regular Binding Arbitration You can also file a lawsuit in district court, though that is more expensive and time-consuming. You cannot do both. Filing in court waives your right to arbitration, and vice versa.
Effects on Your Mortgage and Payment Deadlines
If your mortgage includes an escrow account, a jump in your appraised value ripples directly into your monthly payment. Your lender collects estimated property taxes each month and adjusts that amount when the annual bill changes. Federal regulations require your loan servicer to perform an escrow analysis at least once a year and send you a statement showing any shortage or surplus within 30 days of the computation year ending.9Consumer Financial Protection Bureau. Escrow accounts A shortage spreads over the coming year and raises your monthly payment. For homeowners on a tight budget, that mortgage statement is often the first tangible sign the appraisal went up.
Winning a protest reverses the effect. Once the district adjusts your value downward, your tax bill drops, and the next escrow analysis should produce a surplus or a smaller monthly payment. Some servicers take several months to process the change, so keep your ARB order or settlement documentation handy.
One warning about timing: filing a protest does not pause your payment deadline. Your property tax bill is due by January 31 of the year following the tax year. Missing that deadline triggers a 6 percent penalty plus 1 percent interest in February, with another 1 percent added to each in every following month, and on July 1 the penalty jumps to a flat 12 percent.10State of Texas. Texas Tax Code 33.01 – Penalties and Interest If your protest is still pending when the bill comes due, pay at least the amount you agree is owed by January 31. If the ARB later reduces your value, the taxing units refund the overpayment.