How to get an assessor's income and expense data for your appeal

Last updated 2026-07-11

Why does the assessor's income and expense data matter for an appeal?

The assessor's income and expense data is the raw material behind your assessment, and small errors in it move value by tens of thousands of dollars. Get the numbers they used and you can check their math against reality. In many states, that data is a public record or must be produced once you file an appeal ^[1][2].

When an assessor values a rental house, apartment building, office, or any other income-producing property, they usually rely on the income approach. They estimate how much rent the property could generate, subtract expenses and vacancy, then divide by a capitalization rate to get value. Change one input and the answer swings hard.

The catch is that assessors often use county-wide averages, published surveys, or an internal database instead of the real numbers for your specific property. Say they assumed 5 percent vacancy when your building runs at 12 percent. Or they applied a 30 percent expense ratio when your operating costs eat 45 percent. The value is wrong, and you can prove it. But only if you can see the numbers they used.

That is the whole point of getting the assessor's workpapers before your hearing. You are not fishing for a technicality. You are checking their arithmetic against what the property actually does.

What income and expense data does an assessor actually have?

Assessors who use the income approach keep four kinds of data: owner-filed income and expense questionnaires, their own income model for your parcel, capitalization rate studies, and sometimes a full appraisal report. Each one is worth requesting, and each one gives you a different angle on the assessment.

Start with the questionnaires. Many states and large counties mail annual income and expense surveys to owners of commercial and rental property. New York City's Department of Finance mails Real Property Income and Expense (RPIE) forms to owners of income-producing properties with assessed values above a threshold, currently $40,000 ^[3]. Cook County, Illinois uses a similar questionnaire for multi-unit and commercial parcels ^[4]. When owners file these forms, the data goes into the assessor's database and often feeds the valuation model directly.

Next is the assessor's own income model. This is the spreadsheet or system output showing what income figure they used, what expense ratio they applied, what vacancy rate they assumed, and what cap rate they chose. In many states this model is part of the assessment record and a public document.

Third are cap rate studies. Some assessors conduct them annually. Illinois publishes county-level cap rate studies that its assessors are supposed to use ^[5]. If your assessor picked a different cap rate than their own published study, that gap alone can win an appeal.

Last are full appraisal reports. Large commercial assessments sometimes include one commissioned by the assessor's office. Those reports are generally public once the assessment is set.

Which states require assessors to disclose their income and expense data?

Disclosure rules vary a lot by state, but almost every situation falls into one of three buckets: full public records access, formal pre-hearing discovery, or no automatic disclosure. Most states put the assessor's income model somewhere in the public assessment record, so a records request usually gets you started.

Full public records access is the common case. In most states, assessment records are public documents under freedom of information or open records laws. The income model the assessor used to value your property is typically part of that record. Request it the way you'd request any government document.

Formal pre-hearing discovery kicks in once an appeal is filed. New York's administrative process before the New York City Tax Commission lets petitioners request the assessor's income capitalization worksheets as part of the pre-hearing exchange ^[3]. Illinois statute 35 ILCS 200/16-180 gives parties to a Property Tax Appeal Board hearing the right to inspect and copy documents the other side intends to rely on ^[5].

No automatic disclosure is the hard case. A few states treat the assessor's internal workpapers as deliberative or proprietary. You file a formal open records request, sometimes fight a partial denial, and occasionally go to court. Texas is the classic example. The Texas Public Information Act (Government Code Chapter 552) covers appraisal district records, but some districts assert exceptions and you may have to pull in the Attorney General's open records division ^[6].

Here is how a handful of large states handle it.

State	Primary mechanism	Key statute or rule
New York	Pre-hearing document exchange / RPIE filings	NYC Admin Code § 11-208.1; Tax Commission rules
Illinois	Discovery at PTAB; income questionnaires public	35 ILCS 200/16-180 [5]
California	Assessment appeals board discovery rules	Cal. Rev. & Tax. Code § 1606 [7]
Texas	Public Information Act request to appraisal district	Tex. Gov't Code § 552 [6]
Florida	Pre-hearing exchange; VAB rules	Fla. Stat. § 194.034 [8]
Georgia	Board of equalization hearing; open records	O.C.G.A. § 50-18-70 et seq. [9]

If your state is not on the list, start with your state's general open records statute and your county assessor's website. Most large counties post a public records request form online.

How do you actually request the assessor's data? Step-by-step.

First figure out whether you are inside or outside a formal appeal. If you have already filed, you usually have stronger rights. If you have not filed yet, you can still get assessment records informally in most places. The single best move is to request the data when you file, not after, so it arrives with time to spare.

Before you file an appeal, call or visit the assessor's office and ask for the property record card and any income and expense workpapers for your parcel. Many assessors hand these over without any formality, especially for routine residential or small rental properties. Bring your parcel ID. Some offices post the property record card online through their parcel search tool, so check there first.

If the assessor won't share informally, file a written public records request under your state's open records statute. Address it to the records custodian. Be specific: name the parcel ID, the tax year, and the documents you want (income capitalization worksheet, income and expense questionnaire on file for the subject property, cap rate study used for the assessment year). Most states require a response within 5 to 10 business days, though actual production can take longer ^[6][9].

After you file an appeal, send a written discovery or document request to the assessor's legal representative or the appeal board, citing your state's specific rule. In Florida, Rule 12D-9.025 of the Department of Revenue's Value Adjustment Board rules governs the pre-hearing exchange, and both sides must share evidence at least 15 days before the hearing ^[8]. In California, Revenue and Taxation Code Section 1606 requires the assessor to make the assessment roll and supporting data available to the Assessment Appeals Board and to the petitioner ^[7].

If you get a denial, keep going. A denial is not the end. In Texas, you can ask the Attorney General's Office to review it within a set window ^[6]. Elsewhere, file a complaint with the oversight agency or raise the issue with the appeal board directly. Boards want both sides to see the evidence. A board member who learns the assessor refused to produce their own workpapers is not going to give the assessor the benefit of the doubt.

What if the assessor used income and expense data you submitted? Can you get a copy?

Yes, and this is the first thing to request. If your county sends an income and expense questionnaire and you or a prior owner filed one, the assessor has that form and may have built the income model from it. Ask for a copy of the filed questionnaire for your parcel for the relevant tax year.

This matters for two reasons. First, if the assessor used your submitted numbers but botched the arithmetic or applied the wrong cap rate, you can show the board exactly where the calculation broke. Second, if the assessor ignored your actual submitted data and reached for county-wide averages instead, that is itself grounds to challenge the value. An assessor sitting on real income and expense data for a specific property who then sets value with generic market surveys is on thin methodological ground.

In New York City, RPIE filings feed the valuation of Class 2 and Class 4 properties directly. The Department of Finance publishes its income and expense estimation process in annual capitalization rate reports ^[3]. If your building's RPIE data was on file but the assessment does not reflect it, that gap is exactly what you carry to the Tax Commission.

For Cook County properties, the Assessor's office publishes its income approach methodology for multi-unit and commercial parcels. Request the model output for your parcel, along with the countywide expense and cap rate tables the office uses, and you have everything you need to rebuild the assessment from scratch ^[4].

How do you use income and expense data once you have it?

Getting the data is step one. Now you test four inputs against market evidence: potential gross income, vacancy, expense ratio, and cap rate. Any input that deviates from real numbers for your property or submarket is a point of attack, and the cap rate usually moves value the most.

Check the potential gross income first. The assessor starts with what the property could earn at market rents. Compare their rent assumption to your actual current rents and to comparable properties in the same submarket. If they used $24 per square foot when the evidence supports $19 to $20, flag it.

Check the vacancy and collection loss rate. Assessors often plug in a stabilized vacancy figure from a market survey. If your property runs higher because of location, condition, or tenant type, document it with rent rolls and bank deposits and argue for a property-specific rate.

Check the expense ratio. The assessor deducts a percentage for operating expenses: insurance, maintenance, management, repairs, reserves. If they used 35 percent of effective gross income and your audited operating statements show 48 percent, the net operating income they calculated is too high, and so is the value.

Check the capitalization rate last, because it is often the biggest lever. A cap rate is just the divisor. Higher cap rate, lower value. If the assessor used 6.5 percent and recent sales of comparable properties imply 7.5 to 8 percent, value drops hard. CBRE's cap rate survey, PwC's real estate investor survey, and local commercial broker market reports are all fair evidence ^[10].

The math is stark. A net operating income of $100,000 capitalized at 6.5 percent produces a value of $1,538,462. The same NOI at 7.5 percent produces $1,333,333. That is more than $200,000 in assessed value on a single point of cap rate ^[10]. It runs straight to your tax bill.

Then document everything. Lay the assessor's worksheet, your own reconstructed spreadsheet, and the market evidence side by side. Board members respond to clean math, not complaints.

What if the assessor doesn't use the income approach for your property type?

Then income and expense data matters much less. Assessors value single-family homes and condos with the sales comparison approach, so this playbook does not apply the same way. But rental properties, from two-to-four unit buildings to small apartment complexes, commercial storefronts, and office space, get valued by income all the time.

Not sure which approach the assessor used? Ask. Request the property record card (also called the property record sheet or assessment card, depending on the jurisdiction). It shows the valuation method and usually at least a summary of the inputs. If value came purely from comparable sales, build your appeal around sales comps instead.

Large commercial properties are different. The assessor may run all three approaches (cost, sales comparison, and income) and reconcile them. You can challenge each one separately. The income approach section has its own income, expense, vacancy, and cap rate inputs, and you attack those just as described above.

If you own property in a major market like Los Angeles County or New York City, the assessor publishes methodology documents online. Read them before you request your parcel's data and your records request gets much sharper.

Are income and expense questionnaires confidential? Can the assessor share yours?

Usually yes for third parties, but you can almost always get your own. Most states treat owner-submitted income and expense data as confidential from the public while still letting the assessor use it to set your value and produce it in your appeal. The rules genuinely differ by state, so this is worth checking.

In most states, the data you file with the assessor is off-limits to third parties but accessible to you as the owner and, in many jurisdictions, to the appeal board. The assessor cannot hand your competitors your rent rolls. They can use the data to set your assessment and put it into the record in an appeal.

New York City's RPIE rules say plainly that RPIE data is confidential and not open to public inspection, even though the Department of Finance uses it directly in its income models ^[3]. Florida Statute 193.074 makes income and expense data submitted to the property appraiser confidential and exempt from public records laws, while still letting the appraiser use it for assessment ^[8].

The confidentiality cuts both ways. The assessor cannot show your filed income data to a buyer or a neighbor. But that also means when you request the income questionnaires filed for comparable properties, you may be denied or handed redacted versions. Expect access to your own filed form and to the assessor's aggregate model assumptions, not to your neighbor's confidential filings.

What if the assessor refuses to produce the data or claims it doesn't exist?

"It doesn't exist" sometimes means exactly that, and that can help you. Smaller and rural assessors may not keep detailed income capitalization workpapers. They value properties with a mass appraisal model and thin parcel-specific documentation. Get the lack of records in writing, because it means the assessor cannot prove their income approach inputs at the hearing, which shifts the burden your way in many states.

"It doesn't exist" other times means the assessor valued your income-producing property with the cost or sales approach, not income at all. Again, get that in writing and plan the appeal around it.

If the assessor flat-out refuses to produce records you believe exist and are public, you have options. File a formal complaint with your state's public records oversight body. Raise it at the start of your appeal hearing, where most boards take a dim view of an assessor who withheld evidence. In some states, failure to comply with discovery brings sanctions or adverse inferences against the assessor.

For large commercial appeals with tens of thousands of dollars on the line, an attorney or a certified commercial appraiser (MAI designation) can often pry loose records a self-represented owner cannot. For smaller rentals, persistence with the open records process usually gets there. The TaxFightBack DIY appeal kit includes template public records request letters drafted for income and expense data.

How do timelines and deadlines affect when you can request data?

Request the data when you file the appeal, not after you get the hearing notice. Most hearings give you 15 to 30 days of notice. Wait until then and the assessor may burn the full allowed response time, and the workpapers arrive after your hearing is over.

Some states have formal pre-hearing exchange deadlines. In Florida, evidence must be exchanged at least 15 days before the hearing ^[8]. In Illinois, PTAB appeals can run for months or years, so there is plenty of time for discovery, but local board of review hearings get scheduled fast, which means you request data immediately ^[5].

In California, the Assessment Appeals Board usually schedules hearings many months out, and the board's rules let both sides request documents in the run-up. Revenue and Taxation Code Section 1606 requires the assessor to make supporting data available, and county AAB rules set the specific exchange deadlines, which vary by county ^[7].

Here is the trade-off if you are up against a deadline. File the appeal first to preserve your right, then send the records request right after. Missing the appeal deadline while you wait for data is a far worse outcome than walking into a hearing with incomplete data.

For jurisdiction-specific deadlines, check county assessor pages for markets like Hennepin County, Montgomery County, or Santa Clara, where local rules can differ sharply from state defaults.

What documents should you request in a complete income-approach data package?

Be specific. A vague request gets a vague response. Here is the full list to ask for when you submit a public records request or a formal discovery request.

1. The property record card for your parcel, for the tax year under appeal. 2. The income capitalization worksheet or model output for your parcel, showing gross income, vacancy rate, effective gross income, operating expenses, net operating income, and capitalization rate. 3. Any income and expense questionnaire or survey filed for your parcel for the relevant tax year and the prior three years. 4. The assessor's cap rate study or capitalization rate selection memorandum for your property type and location for the assessment year. 5. The assessor's expense ratio tables or schedules used for your property type for the assessment year. 6. Any appraisal report commissioned by the assessor's office for your parcel. 7. Any comparable rental income data the assessor used to set the market rent assumption for your property.

Send the request in writing and keep a dated copy. If the assessor responds partially, follow up in writing naming exactly which items they left out.

For commercial properties in major markets, add the assessor's neighborhood or submarket income and expense summary tables. These are aggregate documents, not parcel-specific, so they are almost always public and not covered by the confidentiality rules that protect individual owner-submitted forms.

Are there any situations where getting this data is harder than usual?

Yes. Four situations make the process tougher: weak open records laws, recently transferred properties, special use properties, and new construction. Each one has a workaround, and none of them is a reason to skip the request.

States with weak open records laws give assessors broad room to withhold deliberative documents. If your state's law has a broad "deliberative process" exemption, the assessor may claim the income model is an internal deliberative document. Challenge the label. A finalized assessment record is not deliberative.

Recently transferred properties are thin on data. If you just bought the property, the assessor may hold little income and expense history, especially if the prior owner never filed questionnaires. Bring the income evidence yourself: your operating statements, lease agreements, and your own income approach.

Special use properties are the hardest. Hotels, self-storage, and healthcare properties get valued with specialized income models and proprietary data sources. Requesting the assessor's data is still worth it, but rebuilding an independent income approach may take a specialist appraiser.

New construction has no operating history, so the assessor's income model is entirely speculative. Get the assumptions they used and hold them up against published industry stabilization studies for new construction in your property type.

For owners in markets like Gwinnett County or Bibb County in Georgia, note that the Board of Equalization process is informal by design, and Georgia's Open Records Act (O.C.G.A. § 50-18-70) gives you a straight path to assessor records without formal discovery ^[9].

Frequently asked questions

Can I request the assessor's income and expense data before filing an appeal?

Yes, in most states. Assessment records are generally public documents, so you can submit a public records request under your state's open records statute at any time. Many assessors will also share property record cards and income workpapers informally if you call or visit with your parcel ID. Getting the data early helps you decide whether an appeal is worth pursuing.

Does the assessor have to use the income approach for my rental property?

Not necessarily. The income approach is standard for commercial and income-producing property, but many assessors apply it inconsistently, especially for small landlords. If the assessor used the sales comparison approach and got the value wrong, your appeal should focus on comparable sales, not income data. Ask for the property record card first. It shows which method the assessor used.

What is a capitalization rate and why does it matter so much?

A capitalization rate converts a property's net operating income into value: value equals NOI divided by the cap rate. A one-percentage-point change in cap rate can shift value by 15 percent or more. If the assessor used 6.5 percent and comparable sales in your market imply 7.5 percent, the assessed value is materially too high, and that gap is very defensible at a hearing.

How do I know if the assessor's income and expense assumptions are reasonable?

Compare their figures to published benchmarks. CBRE and PwC publish annual cap rate and expense surveys by property type and metro. IREM (Institute of Real Estate Management) publishes detailed income and expense analyses by building type and region. For small multifamily, local broker market reports often carry vacancy and expense data. Any figure that strays far from published benchmarks is worth challenging.

What happens if the assessor refuses to comply with my public records request?

Document the refusal in writing first. Then escalate through your state's open records enforcement mechanism: the Attorney General's office in Texas, the Committee on Open Government in New York, the state ombudsman in Florida, and similar bodies elsewhere. You can also raise the non-disclosure with the appeal board at your hearing. Many boards draw an adverse inference against an assessor who withholds evidence.

Is the income and expense questionnaire I submitted to the assessor confidential?

Usually yes, for third parties. Most states treat owner-submitted income and expense data as confidential and exempt from public records requests by other members of the public. But you, as the owner, can almost always get a copy of your own filing. And the assessor can use your filed data to set your assessment and produce it in an appeal proceeding.

How far back can I request income and expense data from the assessor?

Public records laws typically cover records the assessor currently holds, and most assessors keep records for the period set by state retention schedules, often three to seven years. For an appeal, the most relevant data is the tax year under appeal plus the one or two prior years. Request those years specifically in your open records letter.

Can I use the assessor's cap rate study against them in an appeal?

Absolutely, and it is one of the strongest moves you can make. If the assessor has a published cap rate study and then valued your property at a different cap rate without explanation, that internal inconsistency wrecks their credibility with the board. Cite the assessor's own study, show the rate they actually applied to your parcel, and ask them to explain the gap. They often cannot.

What if my property was assessed using the cost approach, not the income approach?

Income and expense data becomes less central. For cost approach assessments, focus on whether the assessor used the right replacement cost, applied appropriate depreciation for the age and condition of your building, and used accurate land value comparables. Request the assessor's cost approach worksheet, not an income model. The process for getting it is the same: a public records or discovery request.

Do I need a commercial appraiser to interpret the income and expense data I receive?

Not always. If the assessor's model is a straightforward income capitalization worksheet, you can check the math yourself with a spreadsheet. Professional help earns its keep in judging whether the assessor's market rent assumptions, expense ratios, and cap rates fit your specific submarket. For properties assessed above roughly $500,000, a certified commercial appraiser's opinion usually pays for itself.

What is an RPIE form and do I have to file one?

Real Property Income and Expense (RPIE) forms are questionnaires that assessors in some jurisdictions send to income-property owners. New York City requires them annually for properties with assessed values above $40,000. Filing is often mandatory, and late or incorrect filings can trigger penalties or bar you from claiming certain assessment reductions at appeal. Check your county assessor's website to see if an RPIE or similar form applies to your property.

How long does it take to get income and expense data from the assessor?

An informal request at the assessor's office can be filled the same day. A formal public records request typically gets a response within 5 to 10 business days under most state statutes, though complex requests or busy offices take longer. Discovery requests inside a formal appeal follow the board's own schedule, which in some states stretches to 30 to 60 days. Request early.

Can I get income and expense data for comparable properties to strengthen my appeal?

For third-party properties, probably not in full. Owner-submitted income and expense questionnaires are generally confidential. But you can request the assessor's aggregate neighborhood or submarket income and expense tables, which show the market-level assumptions the assessor used. You can also use published commercial data sources (CBRE, PwC, IREM) and broker lease comps to establish what income and expenses should look like for your property type and location.

Sources

1. International Association of Assessing Officers (IAAO), Standard on Mass Appraisal of Real Property: Income-producing properties are typically valued using the income capitalization approach, which requires income, expense, vacancy, and capitalization rate inputs.
2. National Conference of State Legislatures, Property Tax Assessment Overview: Assessment records are generally public documents subject to state open records laws.
3. New York City Department of Finance, Real Property Income and Expense (RPIE) filing requirements: NYC requires RPIE filings for income-producing properties with assessed values above $40,000; data is used directly in the income approach valuation for Class 2 and Class 4 properties and is confidential from public inspection.
4. Cook County Assessor's Office, Income Approach methodology for multi-unit and commercial properties: Cook County uses income and expense questionnaires for multi-unit and commercial parcels and publishes its income approach methodology including countywide expense and cap rate tables.
5. Illinois Compiled Statutes, 35 ILCS 200/16-180, Property Tax Appeal Board discovery: Illinois statute 35 ILCS 200/16-180 gives parties to a PTAB hearing the right to inspect and copy documents the other side intends to rely on.
6. Office of the Texas Attorney General, Texas Public Information Act (Government Code Chapter 552): The Texas Public Information Act covers appraisal district records; owners can ask the Attorney General's office to review a denial of a public information request.
7. California State Board of Equalization, Revenue and Taxation Code Section 1606: California Revenue and Taxation Code Section 1606 requires the assessor to make the assessment roll and supporting data available to the Assessment Appeals Board and to the petitioner.
8. Florida Department of Revenue, Value Adjustment Board rules, Rule 12D-9.025; Florida Statute 193.074 (income data confidentiality); Florida Statute 194.034 (pre-hearing exchange): Florida VAB Rule 12D-9.025 requires both sides to exchange evidence at least 15 days before the hearing; Fla. Stat. 193.074 makes owner-submitted income data confidential from public records.
9. Georgia Secretary of State, Georgia Open Records Act (O.C.G.A. § 50-18-70): Georgia's Open Records Act (O.C.G.A. § 50-18-70) provides a direct path to assessor records without formal discovery.
10. CBRE Research, U.S. Cap Rate Survey: Published cap rate surveys by property type and metro area allow property owners to benchmark the cap rate used by an assessor against current market evidence; a one-percentage-point cap rate difference on $100,000 NOI shifts value by approximately $200,000.
11. Institute of Real Estate Management (IREM), Income/Expense Analysis reports: IREM publishes detailed income and expense analyses by building type and region, usable as benchmarks to challenge assessor expense ratio assumptions.