What is a tax certiorari proceeding and do you need one?

Last updated 2026-07-09

What does 'tax certiorari' actually mean?

Tax certiorari is a court proceeding, usually filed in a state trial court, that challenges the assessed value your local assessor put on your property. The word "certiorari" is Latin for "to be made certain." In general law it means a higher court reviewing a lower tribunal's decision. In property tax, it has a narrower meaning.

New York is where you'll hear the term most. Under New York Real Property Tax Law Article 7, a tax certiorari petition is the statutory way to challenge an assessment after the local Board of Assessment Review has denied or only partly granted your grievance. ^[1] For smaller residential properties, the streamlined version is called Small Claims Assessment Review (SCAR). For larger or more complex cases, it's a full Article 7 petition.

Other states use different names for the same basic idea. In Illinois you appeal to the Property Tax Appeal Board and then to circuit court. In California you go to the Assessment Appeals Board and then to superior court. In New Jersey the Tax Court handles contested assessments directly. The concept holds everywhere: once you've exhausted administrative remedies, you can ask a judge to review whether the assessor got the number right.

So when someone says "we filed a certiorari," they mean a formal legal challenge to an assessment, with a judge as the decision-maker instead of a local review board.

How does a tax certiorari proceeding work, step by step?

Certiorari runs in a fixed sequence, and skipping a step usually kills your right to the next one.

First, you must have received a Notice of Assessment and filed a formal grievance with your local administrative body, usually a Board of Assessment Review or Assessment Appeals Board. You cannot go straight to court in most jurisdictions. ^[1]

Second, after that board issues its final determination (which may still leave your assessment too high), you have a short window to file a petition in court. In New York, Article 7 petitions must generally be filed within 30 days after the final administrative determination, though the exact deadline depends on the municipality's tax calendar. ^[1] Miss that window and the case is time-barred.

Third, once the petition is filed, the case is docketed and the municipality's attorney gets served. Both sides usually exchange appraisals. The assessor's office defends the original value. You present evidence that it was too high. This is where a licensed appraiser earns their fee.

Fourth, most certiorari cases settle. The municipality agrees to cut the assessed value by a negotiated amount, which becomes a refund on taxes already paid plus a lower bill going forward. Both sides settle because trial is expensive.

Fifth, if there's no settlement, the case goes to trial before a judge. No jury hears assessment cases in most states. The judge weighs the competing appraisals and issues a written decision.

In New York City, the city's Tax Commission handles initial reviews, and Article 7 petitions filed in Supreme Court can cover multiple tax years at once after a proceeding is open. ^[2] That multi-year feature is why certiorari appeals to commercial owners who plan to hold a property for years.

Who actually uses tax certiorari, and is it for residential homeowners?

Most residential homeowners don't need certiorari and won't come out ahead by filing one. It's built for high-value property and large dollar stakes.

The proceeding makes financial sense when four things line up:

• The property has a high assessed value and the over-assessment is large in dollars, more than percent.
• The administrative appeal already failed or produced only a token cut.
• The owner plans to hold the property long enough to benefit from multi-year savings.
• A credible appraisal supports a value clearly below the assessor's figure.

For commercial real estate, office buildings, shopping centers, apartment complexes, and industrial sites, certiorari is standard practice in high-tax states. Law firms in New York and New Jersey build whole practices around it. Attorneys usually work on contingency, taking 25 to 33 percent of the first year's tax savings, sometimes with annual renewals. ^[3]

Run the math for a homeowner with a $400,000 assessed value and $8,000 in annual taxes. Knock the assessment down 10 percent and you save $800 a year. A contingency attorney takes a third, leaving you $533. Then subtract court costs and a residential appraisal that runs $500 to $1,500. ^[4] The margin gets thin fast.

New York's SCAR process exists precisely to give residential owners a cheaper, faster alternative to full Article 7 litigation. For properties under the county's applicable value cap, SCAR costs a $30 filing fee and uses a hearing officer instead of a judge. ^[1] That's the right first stop for most New York homeowners.

If your state has no SCAR equivalent and your administrative appeal failed, certiorari may be the only option left. Just start by asking whether the savings justify the fight.

What states commonly use tax certiorari proceedings?

New York uses "certiorari" as a formal label more than any other state, codified in Article 7 of the Real Property Tax Law. ^[1] NYC property owners interact with the process constantly, especially commercial landlords and co-op buildings. If you own property in the city, the nyc property tax system means attorneys file certiorari petitions for buildings of nearly any size almost as a matter of routine.

New Jersey's Tax Court handles assessment challenges that work the same way, though the statutes say "appeal" rather than certiorari. The Tax Court of New Jersey reviews local board decisions and has original jurisdiction over direct-filed assessment appeals for most commercial properties. ^[5]

Illinois allows appeals to circuit court after the Property Tax Appeal Board (PTAB). Cook County owners use this path often. The cook county tax assessor tax bill appeals process has several layers before the courts.

California uses a superior court action after an Assessment Appeals Board decision. Los Angeles and Santa Clara counties both see heavy litigation over commercial assessments. ^[12] The la county property tax and santa clara property tax systems have well-developed administrative appeals that most owners should exhaust first.

Texas has its own judicial review path through district court after the Appraisal Review Board (ARB). Large commercial owners in Bexar County and elsewhere file these suits routinely. The bexar county tax assessor page covers the Texas ARB process in detail.

Most other states have similar judicial review without the certiorari label. The table shows the general structure across several high-activity states.

State	Administrative body	Court review stage	Common name
New York	Board of Assessment Review	Supreme Court, Article 7	Tax certiorari
New Jersey	County Tax Board	Tax Court of NJ	Tax appeal
Illinois	PTAB	Circuit Court	Tax objection / circuit appeal
California	Assessment Appeals Board	Superior Court	Assessment appeal lawsuit
Texas	Appraisal Review Board	District Court	ARB appeal to court
Georgia	Board of Equalization	Superior Court	De novo appeal
Pennsylvania	Board of Assessment Appeals	Court of Common Pleas	Assessment appeal

What does a tax certiorari proceeding cost?

Cost is the number that decides whether you should file, and it swings widely. Filing fees are small. The appraisal and the attorney are what add up.

New York Article 7 filing fees are typically under $200 per parcel. The SCAR filing fee is $30. ^[1] Those are the cheap part.

The real expense is the appraisal. Courts want expert testimony on value, which means a licensed appraiser, often an MAI-designated one for commercial work. A residential appraisal costs roughly $500 to $1,500 for straightforward property. A commercial appraisal on an income-producing building runs $3,000 to $15,000 or more depending on complexity. ^[4] You pay these regardless of outcome in most arrangements.

Attorney fees are either hourly (rare for pure certiorari work) or contingency. Contingency rates in New York and New Jersey typically run 25 to 33 percent of the first year's tax savings, and some firms also take a slice of prior-year refunds. ^[3] On a large commercial case, that's a rational trade. For a homeowner saving $600 a year, you're handing over $150 to $200 annually and still paying the appraisal out of pocket.

Go pro se and you can handle a New York SCAR proceeding yourself for the $30 fee plus any evidence costs. A full Article 7 petition is harder to run alone. The municipality shows up with experienced counsel and the evidence rules are stricter.

County-level appeals, the ones that come before certiorari, are almost always free or nearly so. The montgomery county property tax appeal, like most county-level appeals, costs nothing to file. Exhaust those before you spend a dollar on litigation.

How long does a tax certiorari case take?

Longer than most homeowners expect. Plan on one to five years depending on the state, the court's docket, and whether you settle early.

The administrative appeal at the local board level usually takes two to six months from filing to decision. That stage isn't certiorari, but you have to finish it first.

After you file the certiorari petition, the timeline depends heavily on the court's calendar and how fast settlement happens. In New York State courts outside NYC, most residential cases settle within one to two years. New York City Article 7 cases on commercial property can run three to five years in active litigation, though many settle within 18 to 24 months once appraisals change hands. ^[2]

New Jersey Tax Court has historically carried backlogs of one to three years for contested trials, though settlements close faster. ^[5]

Here's a timing point that matters: in many states, filing a petition preserves your right to refunds for prior tax years, not only the current one. New York proceedings can reach back through prior tax years in some cases. That back-refund window is one reason large commercial owners file nearly every year, since the open petition keeps the door propped.

For homeowners, the multi-year lag means you carry an over-assessed property for a long time before any relief lands. A strong administrative appeal in front of a responsive local board is almost always faster and cheaper.

Do you have to hire a lawyer for tax certiorari, or can you do it yourself?

For New York's SCAR process, you can represent yourself, and it's designed for exactly that. You submit your evidence, appear before a hearing officer (or file documents by mail in some counties), and get a written decision. No attorney required. ^[1]

A full Article 7 petition in New York, or the equivalent court proceeding in other states, is a different animal. Pro se is technically allowed but practically hard. You're filing a legal pleading, serving a government entity, and usually presenting a formal appraisal. Most self-represented owners who get that far hire an attorney eventually anyway.

The better question is whether you should be in certiorari at all, or whether a careful DIY administrative appeal would have gotten you the same result without court costs. Our property tax appeal kit walks through building the strongest administrative case with real comparable sales and assessment evidence, the kind of record that wins at the board level before you ever need a lawyer. Exhausting your administrative remedies fully and aggressively is almost always the right first move.

If you own commercial property in a state with an active certiorari bar, the contingency-fee market exists for good reason. The savings on a $10 million building justify the 30 percent cut. For most single-family homeowners, the math points the other way: a strong DIY administrative appeal first, and certiorari only as a last resort when the stakes are high enough to carry the legal freight.

What evidence do courts look at in a tax certiorari case?

Courts look mainly at market value, meaning whether the assessor's estimate holds up against the evidence you put in front of the judge. The core evidence falls into a few buckets.

Comparable sales (comps). Recent arm's-length sales of similar properties. Courts weigh sale price per square foot, sale dates, location adjustments, and how each comp differs from yours. A homeowner can build a solid comp analysis for an administrative appeal. At the court level, an appraiser usually presents it in a formal report.

Income approach. For income-producing commercial property, courts look at actual income, market rent, vacancy rates, cap rates, and the resulting value. This is where commercial certiorari gets technical and where MAI appraisers earn their fees.

Cost approach. Used for newer buildings or special-use property with few comparable sales. Courts lean on it less for residential cases.

Equalization evidence. In some states you can argue two things: that the property is over-valued in absolute terms, and that it's assessed at a higher ratio of market value than similar properties, which is an equal-treatment argument. New York's Article 7 allows challenges based on both excess assessment and unequal assessment. ^[1]

The assessor starts with the benefit of the doubt in most states. The New York Court of Appeals held in Matter of FMC Corp. v. Unmack (1998) that the assessor's determination carries a presumption of validity, and the petitioner must first overcome that presumption with credible evidence of value. ^[7] So a strong appraisal matters. Saying "my house is worth less" gets you nowhere. You need numbers.

For Georgia homeowners, the gwinnett county tax assessor process and the bibb county tax assessor process both use comparable sales as the primary evidence at the Board of Equalization stage, the administrative step before any court filing. Get your comps right there and court may never be necessary.

What's the difference between a tax certiorari and a regular property tax appeal?

A regular property tax appeal is administrative. A tax certiorari is judicial. That's the core split, and it drives everything else about cost, speed, and who represents the other side.

In a regular appeal, you file with a local board, a hearing officer reviews your evidence, and the board issues a decision. No court. It's usually free or nearly free, faster than litigation, and open to non-lawyers. This is what most homeowners mean by "appealing their assessment."

In a certiorari, a judge decides. The rules of evidence are stricter. Government attorneys almost always appear. The process takes longer and costs more.

The two aren't options you pick between at the start. Certiorari comes after the administrative appeal fails or falls short. In New York, you must file your annual grievance at the local Board of Assessment Review before you have standing to file an Article 7 petition. ^[1] Skip the administrative step and your petition gets dismissed.

The practical sequence for most owners:

1. File the administrative appeal (grievance, county board appeal, or ARB hearing). 2. If denied or under-reduced, decide whether the remaining over-assessment justifies court costs. 3. If yes, file the certiorari petition within the statutory deadline.

For los angeles county property tax challenges, the Assessment Appeals Board is the administrative layer. In Hennepin County, Minnesota, there's a local board first, then hennepin county property tax owners can petition Tax Court. The names change by jurisdiction. The two-stage structure is nearly universal.

When should you skip certiorari and just do the administrative appeal yourself?

Most of the time, for most homeowners, skip certiorari and do the administrative appeal yourself. It's your highest-leverage move: free, fast, and often decided within six months.

Boards see thousands of cases and settle many because they know the assessor's data has errors. The National Taxpayers Union Foundation has estimated that homeowners who appeal win some form of reduction in roughly 40 to 60 percent of cases, depending on jurisdiction, with successful reductions averaging around 15 percent in studies of county-level data. Nobody has rigorously consistent national numbers on this, so treat it as a range, not a promise. ^[8]

Take a homeowner whose $350,000 assessed value should be $300,000. A successful administrative appeal saves roughly $1,500 to $2,500 a year at a 2 percent effective tax rate. That's real money, and you get it without a lawyer, without court costs, and often within half a year.

Certiorari makes sense when:

• Your administrative appeal was denied and the assessment is still 15 percent or more above supportable market value.
• The annual overcharge tops roughly $3,000 to $5,000, a rough point where legal fees start to earn their keep.
• You have, or can commission, an independent appraisal that clearly supports a lower value.
• The property is commercial, income-producing, or high-value residential.

If your state has an intermediate appeal level between the local board and the courts (New York's Tax Commission for NYC properties, Illinois's PTAB), use it before going to court. Each administrative level is cheaper and faster than the judicial one above it. Only after you've run out of administrative options, with the money still justifying it, does certiorari earn a look.

What are the deadlines for filing a tax certiorari petition?

Deadlines vary by state and sometimes by municipality, and they're almost always hard cutoffs with no forgiveness for missing them. In New York the window is 30 days; in California it's six months. Get the exact date from your county before you rely on any general figure.

In New York, the deadline to file an Article 7 certiorari petition is generally 30 days after the final determination of the Board of Assessment Review (or the Tax Commission in NYC). ^[1] For NYC property, the Tax Commission review period and the Article 7 filing window interact in a way that requires tracking specific tax-calendar dates, which vary by tax class.

In New Jersey, assessment appeals to the county tax board must be filed by April 1 of the tax year (or April 1 following a revaluation in a revaluation year). Appeal the county board's decision to Tax Court and you generally have 45 days from the county board judgment. ^[5]

In Texas, a property owner who loses at the ARB has 60 days to file suit in district court. ^[9]

In California, after the Assessment Appeals Board issues its final decision, you have six months to file a superior court action. ^[12]

In Georgia, after the Board of Equalization's decision, property owners have 30 days to appeal to superior court. ^[5]

The table in the state overview section gives the framework, but always confirm the specific deadline with your county assessor's office or your state's tax authority. The penalty for missing it is almost always the permanent loss of your right to challenge that year's assessment. There's no extension for "I didn't know."

For Missouri owners, the st louis county personal property tax page covers the Board of Equalization and the appeal timeline for that jurisdiction.

Does filing a tax certiorari petition guarantee a refund?

No. Filing starts the process. It guarantees nothing about the outcome.

The assessor's determination carries a presumption of correctness in most states. ^[7] You carry the burden of proving the assessment is wrong. If your evidence is thin or your appraisal doesn't survive cross-examination, the court can affirm the original number. A small number of jurisdictions even let assessors counterclaim for a higher value, though that's rare and usually limited to clear undervaluation.

What filing does guarantee, in many states, is that the tax years covered by the petition stay open for a potential refund. Settle for a reduction two years after filing and you typically get refunds with interest for each of those years. The interest rate is set by statute and varies by state. New York pays interest on over-assessed amounts at a statutory rate that has historically run a few points above prime. ^[1]

Refunds come from the municipality, not the state. On large commercial cases, municipalities sometimes stretch multi-year refunds to soften the budget hit. That's a negotiated settlement term, not an automatic right.

Before you count on a refund, talk to a tax attorney in your state about the realistic settlement range for your property type and the track record of your county's assessor's office. Past settlement rates tell you your real odds.

Frequently asked questions

Is tax certiorari the same thing as filing a property tax appeal?

Not exactly. A standard property tax appeal is administrative, handled by a local board at little or no cost. Tax certiorari is a court proceeding filed after the administrative appeal fails. It's the next step up, not an alternative to the initial appeal. In most states you must finish the administrative appeal first before you have standing to file certiorari in court.

Does New York's Small Claims Assessment Review (SCAR) count as certiorari?

SCAR is a simplified version of the Article 7 certiorari process built for residential homeowners in New York. It's technically a tax certiorari proceeding, but it uses a hearing officer instead of a judge and costs $30 to file. It's available for owner-occupied residential property under applicable assessed-value limits. Most New York homeowners should use SCAR rather than a full Article 7 petition.

Can I file a tax certiorari petition without an attorney?

For New York's SCAR process, yes, and many homeowners do it well. For full Article 7 petitions or equivalent court filings elsewhere, you can technically appear pro se, but you'll face experienced government attorneys and evidence rules that assume a formal appraisal. Most self-represented petitioners without an appraisal lose. The administrative appeal, which you can handle yourself, is almost always the smarter first move.

How much of my taxes can I actually get back if I win a certiorari case?

You recover the difference between what you paid and what you would have paid at the corrected assessment, for each year the petition covers, plus statutory interest. In New York, a proceeding can often cover multiple prior tax years once it's open. The refund depends on how large the reduction is and how many years the petition reaches. There's no cap on the amount, but it's limited to documented overpayment.

What happens if I miss the deadline to file a tax certiorari petition?

You permanently lose the right to challenge that year's assessment in court. There are almost no exceptions. The deadlines are jurisdictional, meaning a court can't grant relief even if your case is strong. Your next chance is the following tax year's administrative appeal cycle. That's why tracking your assessment notice dates and grievance deadlines matters so much.

Do contingency-fee attorneys take tax certiorari cases for homes, or just commercial properties?

Most contingency-fee certiorari attorneys focus on commercial property because the savings justify the work. Some firms take residential cases in New York, but usually only for higher-value homes where potential savings top several thousand dollars a year. For average-value houses, the math rarely favors the attorney, so homeowners are better served by SCAR or a DIY administrative appeal.

What's the difference between tax certiorari in New York and a Tax Court appeal in New Jersey?

Both are judicial challenges to a property assessment after administrative remedies run out. New York uses the Article 7 certiorari petition filed in Supreme Court. New Jersey goes to Tax Court, which has original jurisdiction over most commercial appeals and hears residential cases appealed from county tax boards. The legal standards and evidence requirements are similar, but the procedural rules and timelines differ between the two states.

Can filing a certiorari petition cause my assessment to increase?

In most states, no. Assessors generally can't raise your assessment as a penalty for challenging it. A small number of jurisdictions allow the assessor to counterclaim if they think the property is underassessed. That's uncommon and usually applies only where the original number is clearly low. In standard residential cases it isn't a realistic risk, but ask a local tax attorney if your state's rules are unclear.

Does every state call this process 'tax certiorari'?

No. New York uses the term most formally. Other states call the same judicial challenge a 'tax objection,' an 'assessment appeal to circuit court,' a 'Tax Court appeal,' or a 'de novo appeal to superior court.' The label doesn't change the concept: a court-level challenge to an assessor's valuation after administrative options are exhausted. Check your state's property tax appeal statutes for the correct terminology and procedure.

How do I know if my over-assessment is big enough to justify certiorari?

Calculate the annual tax savings if your assessment dropped to market value. Multiply by the years you'll likely hold the property. Subtract appraisal costs ($1,500 to $5,000 depending on property type) and attorney contingency (25 to 33 percent of first-year savings if you use one). If the net figure is clearly positive and the administrative appeal already failed, certiorari may be worth it. For most homeowners saving under $2,000 a year, it's a close call.

What is an 'equalization rate' and does it matter in certiorari?

An equalization rate is the ratio of a municipality's assessed values to actual market values, set by the state. In New York, an equalization rate below 100 percent means properties are assessed at a fraction of full market value. Courts use the rate to convert assessed value into implied market value and compare it to your evidence. A low rate can help your case if the assessor didn't apply it consistently to your property.

Can a co-op or condo owner in New York City file a tax certiorari petition?

Individual co-op shareholders generally can't file Article 7 petitions, because the building, not the shareholder, is the assessed property. The co-op corporation must file. Condo owners in New York City can challenge their individual unit assessments. This is one reason co-op boards retain certiorari counsel to file for the whole building, with savings flowing through to shareholders as lower maintenance charges.

Does paying my property taxes under protest preserve my certiorari rights?

In some states, yes: you must pay under written protest to preserve refund rights if you win. In New York, you generally don't need to pay under formal protest to file certiorari, but you must pay to avoid penalties. In Texas, unpaid taxes can affect your standing to appeal. The rule varies, so check your state's statute or the county assessor's guidance before you withhold any payment.

How is tax certiorari different from suing the assessor personally?

Tax certiorari isn't a suit against the assessor as an individual. It's a proceeding against the assessment itself, naming the taxing authority (city, county, or school district) as the respondent. Assessors acting within their official duties have broad immunity from personal liability. Certiorari challenges the number the assessor assigned, not the person. If you win, the municipality pays the refund, not the assessor.

Sources

1. New York State Legislature, Real Property Tax Law Article 7: Article 7 of the New York Real Property Tax Law is the statutory vehicle for judicial review of property assessments, including SCAR ($30 filing fee) and full certiorari petitions, with a 30-day filing window after the Board of Assessment Review's final determination.
2. New York City Tax Commission: The New York City Tax Commission conducts initial administrative reviews of assessments, and Article 7 petitions filed in Supreme Court can cover multiple tax years once a proceeding is open.
3. New York State Bar Association, Real Property Law Section: Contingency fee arrangements for tax certiorari typically run 25 to 33 percent of the first year's tax savings.
4. Appraisal Institute: Residential appraisals for litigation purposes typically cost $500 to $1,500; commercial appraisals range from $3,000 to $15,000 or more depending on property complexity.
5. New Jersey Courts, Tax Court: The New Jersey Tax Court has jurisdiction over property assessment appeals; county tax board appeals must generally be filed by April 1 of the tax year, with 45 days to appeal a county board decision to Tax Court.
6. New York Court of Appeals, Matter of FMC Corp. v. Unmack, 92 N.Y.2d 179 (1998): New York courts have held that an assessor's determination carries a presumption of validity that the petitioner must overcome with credible evidence of value.
7. National Taxpayers Union Foundation, Property Tax Assessment Research: Studies of county-level appeal data suggest homeowners who appeal win some form of reduction in roughly 40 to 60 percent of cases depending on jurisdiction, with successful reductions averaging around 15 percent.
8. Texas Comptroller of Public Accounts, Property Tax Taxpayer Remedies: In Texas, property owners have 60 days after an ARB order to file suit in district court challenging the assessment.
9. Lincoln Institute of Land Policy, Significant Features of the Property Tax: Effective property tax rates and appeal procedures vary significantly by state and county; California requires a superior court action within six months of an Assessment Appeals Board decision.