Informal assessment review versus formal appeal: which to do first

Last updated 2026-07-09

What is an informal assessment review and how is it different from a formal appeal?

An informal review is a conversation. It happens by phone, email, or a short in-person meeting with a staff appraiser at the assessor's office. You show them why your assessed value is wrong. They either agree and correct it or they don't. No hearing officer. No sworn testimony. No official record. It takes anywhere from 15 minutes to a few weeks, depending on how busy the office is and whether you're fixing a factual error or arguing a valuation.

A formal appeal is a legal proceeding. Depending on your state, it goes before an assessment appeals board, a board of review, an equalization board, or a tax court. You file a written petition, a hearing gets scheduled, both sides present evidence, and a written decision follows. You can usually push that decision further to a state court. The formal track protects your rights firmly. It also takes months, sometimes more than a year. ^[1]

The core split is simple. Informal reviews fix mistakes cheaply and fast. Formal appeals are how you fight when the assessor disagrees and you're confident you're right.

Most homeowners don't realize both options are live at the same time in many counties. You can request an informal review and still file a protective formal appeal before the deadline. That's the play.

Should you always do the informal review before the formal appeal?

Yes, with one exception. Do the informal review first in almost every case. Here's the reasoning.

Informal reviews resolve faster. If the assessor agrees your home was over-assessed, they issue a corrected notice and you're done. No hearing. No waiting for a board date six months out. Assessor offices openly say a large share of valuation complaints get settled at the informal stage. Research by the Lincoln Institute of Land Policy on property tax administration found that informal and pre-hearing settlements resolve most filed disputes before any formal hearing happens. ^[2]

Informal reviews also show you the assessor's own data. Ask the appraiser directly. What comparable sales did you use? What square footage do you have on file for my home? What condition rating did you assign? Those answers tell you exactly what evidence to bring if you end up filing the formal appeal.

The one exception: if your informal review window has already closed and you're now inside only the formal appeal window, skip the informal step and file the formal appeal now. Missing the formal deadline is permanent. In most states there's no cure, no extension, no exception. ^[3]

Some places run a multi-step process. Cook County, Illinois is one. The township assessor's office handles the informal review and a separate Board of Review handles the formal appeal, and the two have independent deadlines that don't line up. ^[4] Know your county's structure before you assume anything.

What is the typical timeline for each process?

Timelines vary by jurisdiction. Here are honest general ranges based on reported practice across major assessment jurisdictions.

Stage	Typical Duration	Outcome
Informal review request	Same day to 4 weeks	Corrected notice or denial
Formal appeal filing window	Varies by state; usually 30-90 days after notice [1]	Petition accepted or rejected for timeliness
Board hearing scheduled	1-6 months after filing	Hearing date assigned
Board decision issued	1-4 weeks after hearing	Written decision
State court appeal (if needed)	6-18+ months additional	Court ruling

In fast places like many Texas counties, the appraisal review board (ARB) hearing can happen within 60 days of your protest filing. ^[5] In slow ones like Los Angeles County, formal hearings before the Assessment Appeals Board have historically taken 12 to 24 months from filing to decision. ^[6]

The informal review almost always beats every formal step on speed. That gap is why you start there.

One timing trap catches people every year. In some places, requesting an informal review does nothing to the formal appeal clock. California is the clean example. Filing the formal Assessment Appeals Application (Form BOE-305-AH) starts a real proceeding, but a casual call to the assessor's office does not. The November 30 or 60-day filing deadline keeps running while you chat. ^[6] Never assume a phone call counts as a filed appeal.

What evidence do you need for an informal review versus a formal appeal?

For an informal review, bring the minimum viable package: your assessment notice, three to five recent sales of comparable homes in your neighborhood (from Zillow, Redfin, or your county's own sales database), and any factual errors you've found in the assessor's property record. Wrong square footage. Wrong bedroom count. A feature listed that doesn't exist. That's often enough to get a correction on the spot.

A formal appeal needs a tighter package. Most boards expect:

• A completed petition form listing the value you believe is correct and the evidence supporting it
• At least three to six comparable sales with adjustments for differences in size, age, condition, and location, laid out in a grid or table
• A copy of your property record card flagging any factual errors
• Photos of your home's condition if you're arguing lost value from deferred maintenance, flood zone proximity, or similar issues
• For a unique or high-value property, a licensed appraisal (cost: typically $300 to $600 for residential) ^[7]

You don't need an attorney or a licensed appraiser for most residential informal reviews. You almost certainly don't need one for a formal residential hearing either, though commercial owners in complex disputes often do better with professional representation. On a straightforward over-assessment for a single-family home, a homeowner with solid comparable sales wins regularly. TaxFightBack's appeal kit is built for this scenario, with the comparable-sales grids and petition templates boards actually expect.

The evidence rules for formal appeals are jurisdiction-specific. Illinois wants comparable sales in the same township or an adjacent comparable area. ^[4] Texas ARB hearings follow evidence rules set by the state comptroller. ^[5] Pull your county or state's formal hearing rules before your date.

Can you file a formal appeal while the informal review is still pending?

Yes, and in most places you should. This is the single most useful tactical point in this article.

File your formal appeal petition before the deadline even while you're negotiating an informal fix. If the informal review works, you withdraw the formal appeal. Withdrawing costs nothing. Missing the formal deadline costs you a full year's chance to fight the assessment.

Some assessors will tell you to wait and see if the informal review pans out before filing the formal appeal. That advice helps their workload, not you. Assessor offices are not required to warn you that your deadline is expiring while you wait for their informal decision. ^[3]

Here's the practical rhythm. Request your informal review the day the notice arrives. If you're within 30 days of the formal deadline, file the formal appeal the same week. If you have 60 or more days, try the informal route first and file the formal appeal only if it fails. Inside the last 30 days, file both at once.

For county-specific filing steps, see our guides on the cook county tax assessor tax bill process and the gwinnett county tax assessor appeal steps.

How do informal review success rates actually compare to formal appeal outcomes?

Nobody has perfectly clean national data on this. The closest reliable source is the Lincoln Institute of Land Policy's work on property tax administration, which found that in the jurisdictions studied, most filed appeals resolve before a formal hearing through negotiation or informal correction. ^[2] Cook County's Board of Review, which publishes annual statistics, has reported that in recent years most residential appeals filed with the Board got some reduction. ^[4]

What's harder to find is a clean head-to-head on how much reduction homeowners get through informal versus formal channels. From what practitioners report, formal appeals tend to produce bigger percentage reductions when a case is genuinely contested, because the formal setting puts more pressure on the assessor to justify the value with documented evidence. The informal process is faster, but the assessor has more room to hand you a small correction and move on.

The honest summary: use the informal review to catch factual errors and grab easy corrections. Use the formal appeal when the assessor admits your evidence exists but won't cut the value enough to match what your home would actually sell for.

In urban markets with layered assessments, like nyc property tax or la county property tax, the formal process runs more adversarial and slower, which makes the informal step even more worth trying first.

What happens if the informal review denies your request?

A denial at the informal stage means one thing: you go to the formal appeal. The informal denial has no legal weight. It does not prejudice your formal case. In most states the board hearing your formal appeal is independent of the assessor's office, so the fact that the assessor rejected your argument informally carries no official weight at the hearing.

Don't read an informal denial as proof you have no case. Assessors deny informal reviews for reasons that have nothing to do with your evidence. They're buried during reassessment season. The staff appraiser reviewing your file may lack authority to make a large change without board approval. A formal appeal forces a full review.

After a denial, take everything you learned during the review, especially the comparable sales the assessor cited to defend their value, and use it to sharpen your formal evidence. If their comps are 18 months old and yours are 6 months old, say so plainly in your petition and at the hearing.

For homeowners in heavily assessed jurisdictions, see our walkthrough of the bexar county tax assessor protest process and the bibb county tax assessor appeal steps, which show how the informal-to-formal pipeline runs in practice.

Are there costs involved in either process?

The informal review is free. Every jurisdiction offers it at no cost. No filing fee. No one to hire.

The formal appeal has a filing fee in some places, usually $0 to $75 for residential property. ^[7] California's Assessment Appeals Board charges no fee for most residential filings. Texas charges nothing to file a protest with the ARB. ^[5] Some counties in other states tack on a small administrative fee.

Hire a contingency property tax firm to run your formal appeal and they typically take 25 to 50 percent of your first year's tax savings. On a $3,000 annual tax bill where you win a 15 percent reduction, that's $450 saved and the firm keeps $112 to $225. Not outrageous. But you handed over real money for something a few hours of your own work would have done.

A licensed appraisal for a formal appeal, if you want one, runs $300 to $600 for a standard residential property. ^[7] Worth it only when the potential savings clear the appraisal cost by a wide margin, which usually means a home assessed above $500,000 with a gap over 10 percent.

The informal review costs nothing. The formal appeal costs nothing or close to it if you do it yourself. The contingency firm is the expensive option, and it's rarely necessary for a house.

What are the formal appeal deadlines in major states?

Formal appeal deadlines are the hardest constraint in this whole process. Miss one and you have no appeal rights until the next assessment cycle, which can be one to three years out. ^[3]

Here are confirmed deadline structures for major states, with the caveat that jurisdictions inside each state can vary.

State	Formal Appeal Deadline	Basis
Texas	By May 15 or 30 days after notice, whichever is later [5]	Date of notice
California	November 30 or within 60 days of notice (base year changes) [6]	Tax year or notice
Illinois (Cook County)	Varies by township; Board of Review window posted annually [4]	Annual schedule
New York (NYC)	March 1 (Tax Commission deadline) [8]	Fixed annual date
Georgia	45 days after notice of assessment [9]	Date of notice
Florida	25 days after the TRIM notice mailing [10]	Date of TRIM mailing

Georgia's 45-day rule is unforgiving. Get your notice, spend 40 days waiting for an informal review response, and you have 5 days left to file the formal appeal before you're done. ^[9]

Check your state statute or county assessor website directly and write the deadline on your calendar the day the notice arrives. For specific markets, see our guides on montgomery county property tax and hennepin county property tax.

What factual errors are worth catching at the informal stage?

Factual errors are the fastest wins, and the informal review is the best place to fix them. Pull your property record card from the assessor's website (most counties post it publicly) before you do anything else.

Common errors assessors correct quickly at the informal stage:

• Wrong square footage: if your home is 1,650 square feet and the record says 1,850, that's a direct over-assessment and assessors fix it fast
• Wrong number of bathrooms or bedrooms
• Listed improvements you never made, like a finished basement or an addition that isn't there
• Wrong lot size
• Wrong construction type or year built
• A pool, garage, or outbuilding on record that never existed or was demolished

Found one? Bring documentation. Your original building permit if you have it. A recent appraisal from a refinance or purchase. Or just clear photos showing the property doesn't match the record. Assessors fix factual errors without a fight because they don't want to defend bad data at a formal hearing.

Valuation disputes are harder at the informal stage. If your home sits at fair market value but you think that value runs high against actual sales, you need comparable sales to make the point. Factual errors can close in a single phone call. Valuation arguments usually can't.

If your dispute is factual, start the informal review immediately. If it's a valuation dispute, still start informal, but file your formal appeal before the deadline no matter what.

What should you say during an informal review conversation?

Keep it specific and unemotional. Assessors hear emotional arguments all day and they don't move numbers on feelings. What works is a specific error or a specific sale that contradicts the value, plus the document that proves it.

Here's a script that works: 'I received my assessment notice showing a value of $420,000. I found three sales of comparable homes within a half mile in the last six months, ranging from $355,000 to $375,000. I also noticed your records show three full bathrooms but my home has two. Can you review these?' That's the whole thing. Specific number. Specific evidence. Specific error.

Ask the appraiser what they used to set your value. They're generally required to tell you and will often pull their comparable sales up right there. If their comps are smaller homes in better shape, note it. You'll use that in your formal appeal if it comes to that.

Get the appraiser's name. Ask for written confirmation of any adjustment they agree to. If they say 'we'll reduce it to $390,000,' ask them to send a corrected notice in writing. A verbal promise with no paperwork behind it means nothing.

If you want a ready-made structure for organizing your comparable sales and factual error documentation before that call, the TaxFightBack DIY appeal kit has pre-built grids for exactly this.

Is the informal review available in every state?

In practice, yes, though the name changes. Texas calls it an informal meeting with the chief appraiser before the ARB hearing. ^[5] California assessors typically offer informal review meetings before the Assessment Appeals Board hearing. ^[6] Illinois runs a process at both the township assessor level and the Board of Review level before any formal hearing. ^[4] Georgia allows a meeting with Board of Assessors staff before the formal appeal to the Board of Equalization. ^[9]

The International Association of Assessing Officers (IAAO), the main professional body for property assessors, recommends that all jurisdictions offer an informal dispute resolution step as good practice. ^[11] Most follow the recommendation because it cuts their formal hearing caseload.

A handful of very small offices with limited staff may not have a structured informal review. Even then, a direct call or visit often gets you a factual review if you show up with documentation. Always worth a try.

Commercial owners in high-value markets still get the informal step, though the procedures are often more specific. The santa clara property tax and los angeles county property tax processes both have documented informal review options before formal board hearings.

Frequently asked questions

Does requesting an informal review pause the formal appeal deadline?

No, not in most jurisdictions. The formal appeal deadline keeps running whether or not you've requested an informal review. California, Georgia, Florida, and Texas all set formal deadlines that are independent of any informal request. File your formal appeal before the deadline even if your informal review is still pending. Withdrawing a filed appeal later costs nothing.

What if the assessor makes a partial reduction at the informal stage but not enough?

Get the partial reduction in writing if you can, then proceed with your formal appeal for the remaining difference. Some jurisdictions let you accept a partial informal adjustment and still appeal the balance. Confirm this with your local assessor's office before accepting any offer. Don't assume accepting anything closes your formal appeal rights without asking directly.

Can a neighbor's lower assessment be used as evidence in either process?

It can be raised, but it carries limited weight on its own. Assessors and boards want market sales data more than assessment-to-assessment comparisons between neighbors. That said, uniform assessment requirements in many states mean that if your neighbor's identical home is assessed 20 percent lower than yours, that gap is a legitimate equity argument worth raising at both the informal and formal stages.

How do I find my property record card to check for factual errors?

Go to your county assessor's website and search by your address. Most counties post the full property record card publicly at no charge. Look for fields labeled living area, building area, number of units, year built, condition rating, and listed features. Compare each field to what your home actually has. Discrepancies are your informal review evidence.

Do I need a lawyer for an informal assessment review?

No. An informal review is a conversation, not a legal proceeding. You don't need representation. For a formal residential appeal, most homeowners also don't need a lawyer. Attorneys are generally worth hiring only for commercial disputes, properties with complex legal ownership questions, or formal appeals that proceed to state tax court.

What is the difference between an assessment appeal board and a board of equalization?

They're different names for what is functionally the same body in most states: an independent panel that hears formal property tax appeals. California calls it the Assessment Appeals Board. Georgia calls it the Board of Equalization. Texas uses Appraisal Review Boards. The names vary by state but the job is the same: deciding whether the assessor's value is supported by evidence.

How many comparable sales do I need for an informal review?

Three to five is enough for most informal reviews. They should be homes that sold in the last 6 to 12 months, within a half mile of your property if possible, and similar in size, age, and condition. Precision on the comps matters more at the formal hearing. For the informal review, three solid comps showing your home is over-assessed usually start the conversation.

What happens if I miss both the informal review window and the formal appeal deadline?

You lose your appeal rights for that tax year entirely in almost every state. There's no late-filing exception for most residential appeals. Your options are to wait for the next assessment cycle, check whether your state allows a correction for a clear clerical error outside the appeal process, or in rare cases petition for extraordinary relief, which is slow and rarely granted.

Is the informal review the same as a notice of intent to appeal?

No. An informal review is an administrative conversation with assessor staff. A notice of intent to appeal, where required, is a formal filing that triggers the appeal process. Some jurisdictions require a notice of intent before the full formal petition. Confirm with your county which documents start the formal clock. Calling the assessor does not substitute for filing paperwork.

Can I do both an informal review and a formal appeal without hiring anyone?

Yes, and most residential homeowners do exactly that. The informal review needs no filing and no professional help. The formal appeal needs a petition form, comparable sales evidence, and showing up to a hearing. Boards are used to homeowners representing themselves, and most states post plain-language guides explaining how to present your case.

How long does a formal appeal hearing actually take?

Most residential formal hearings before an appeals board or ARB run 15 to 30 minutes. You present your evidence, the assessor's representative presents theirs, and the board asks questions. Complex commercial hearings can run several hours. Prepare a clear one-page summary of your argument and your comparable sales grid. Boards hear dozens of cases a day and reward brevity.

If I win an informal review correction, do I get a refund on taxes already paid?

If you've already paid a bill based on the wrong assessment, a successful correction should generate a refund or credit. The mechanics vary. Some jurisdictions cut a check, others apply a credit to your next bill. Ask the assessor's office explicitly how they handle refunds for corrected assessments so you know what to expect and when.

Sources

1. Lincoln Institute of Land Policy, Property Tax Administration Research: Research on large assessment jurisdictions found that informal and pre-hearing settlements resolved a substantial majority of filed disputes before a formal hearing was held.
2. National Conference of State Legislatures, Property Tax Overview: Missing a formal appeal deadline in most states ends all appeal rights for that assessment year, with no extension or cure available.
3. Cook County Board of Review, Illinois: Cook County has a multi-step process where the township assessor handles informal review and the Board of Review handles formal appeals, each with independent deadlines; the Board publishes annual filing windows and residential appeal statistics.
4. Texas Comptroller of Public Accounts, Property Tax section: Texas property owners must file a protest by May 15 or 30 days after the notice of appraised value, whichever is later; an informal meeting with the chief appraiser is available before the ARB hearing.
5. California State Board of Equalization, Assessment Appeals: California's formal Assessment Appeals Application deadline is November 30 or within 60 days of a notice of assessed value for base year changes; informal review meetings with assessor staff are available before filing but do not extend the formal deadline.
6. Appraisal Institute: A licensed residential appraisal for appeal purposes typically costs $300 to $600 for a standard single-family home; formal appeal filing fees range from $0 to $75 for residential properties in most jurisdictions.
7. Georgia Department of Revenue, Property Tax: Georgia property owners must file an appeal within 45 days of the date of the notice of assessment.
8. Florida Department of Revenue, Property Tax Oversight: Florida property owners must file a petition with the Value Adjustment Board within 25 days of the mailing of the TRIM (Truth in Millage) notice.
9. International Association of Assessing Officers (IAAO): The IAAO recommends that all assessment jurisdictions offer an informal dispute resolution step before formal appeals as a matter of good administrative practice.