Mercer County PA Tax Assessment: Reassessment, Appeals, and Relief

To challenge your new value, file a Mercer County PA tax assessment appeal with the Board of Assessment Appeals through the Tax Assessment Office at the courthouse in Mercer. Final assessed values from the county-wide reassessment will be mailed in July 2026, and every formal appeal must be completed by October 31.¹ Miss that date and you live with the value until the next appeal cycle.

Why Values Are Changing in 2026

Mercer County spent more than 50 years pegging assessed values to 1970 levels and using a state-provided Common Level Ratio to convert current prices back to that baseline. The gap grew too wide to manage, and the county hired Tyler Technologies to conduct a full reassessment that began in 2023 and finishes in 2026. New assessed values will appear on 2027 tax bills.

The reassessment itself is not designed to raise revenue. Pennsylvania law requires the county, municipalities, and school districts to adjust their millage rates once the new values are certified so each taxing body collects the same total in 2027 as it did in 2026.¹ Your individual bill can still move up or down depending on how your new value compares to the county-wide shift, which is exactly why the appeal window matters.

Filing the Formal Appeal

Your final value notice arrives in July 2026. From that point, you have until October 31 to file with the Board of Assessment Appeals. Appeals and any fees go through the Mercer County Tax Assessment Office at the courthouse in Mercer.¹

The residential appeal form asks for your name, mailing address, property address, municipality, parcel number, property type, the date you acquired the property, and the purchase price. There is a comparable sales section where you list the names, addresses, and sale prices of similar properties supporting the value you’re claiming, plus a space to state your reason for appealing.²

If Tyler Technologies already adjusted your tentative value during the free informal reviews earlier in 2026, that change carries through to the July notice. You can still file a formal appeal on top of that if you believe the final value is wrong.

Evidence That Actually Matters

Filing the form is the easy part. Winning turns on what you bring to support a lower value.

A professional appraisal from a certified Pennsylvania appraiser is not required by the form, but it is the strongest single piece of evidence.
If you bought the property recently, a settlement statement showing your actual purchase price carries significant weight.
Photographs of structural problems, flood damage, deferred maintenance, or any condition that reduces value can support your case.
The comparable sales you list should be genuinely comparable in size, age, condition, and location. Owners commonly stumble here by listing the cheapest nearby sales rather than the most similar ones.

If the assessor’s record shows the wrong square footage, the wrong number of bedrooms, or missed a condition problem, bring proof. Errors in the underlying property data are among the easiest arguments for the board to accept.

The Hearing and the Board’s Decision

Once filed, you’re scheduled for a hearing before the Board of Assessment Appeals. The hearings are relatively informal. You or your representative present your evidence, and the board reviews appraisals, comparable sales data, photographs, and any other documentation.

You’ll get a written decision by mail within 15 days of the hearing.³ Under state law, all board decisions must be finalized with written notice no later than November 15.⁴

If the Board Rules Against You

You can push the appeal further by filing for a hearing before a court-appointed Master. This filing goes through the Mercer County Office of the Prothonotary rather than the Tax Assessment Office, and the filing fee is $134.00.⁵

A Master hearing is more formal than the board proceeding. Most owners at this stage retain an attorney or an experienced tax consultant, and a professional appraisal becomes close to essential if you don’t already have one. The Master reviews the evidence independently and issues a recommendation to the Mercer County Court of Common Pleas. Add up the filing fee, attorney costs, and appraisal expense before committing. The projected tax savings need to justify what you’re spending to get them.

Appealing an Interim Assessment

The October 31 deadline applies to the county-wide reassessment and to annual appeals. Interim assessments are different. When new construction, a major renovation, a subdivision, or a demolition changes a property, the Tax Assessment Office issues an interim notice with its own shorter appeal window. If you receive one, file with the Board of Assessment Appeals through the Tax Assessment Office promptly, following the same procedure. The office can be reached at 724-662-7551 for questions about interim notices and deadlines.⁶

Relief Programs to Check While You’re Appealing

An appeal lowers your assessed value. These state programs lower what you actually pay, and they run independently of the reassessment.

Homestead and Farmstead Exclusion

If you own and live in your home as your primary residence, the Homestead Exclusion reduces the taxable assessed value used for school taxes. Farms of at least ten contiguous acres with buildings used for commercial agricultural production may qualify for the Farmstead Exclusion. Applications must be filed by March 1 preceding the tax year in which you want the relief.⁷

Property Tax/Rent Rebate

Pennsylvania residents 65 and older, widows and widowers 50 and older, and people with disabilities 18 and older may qualify for a rebate of up to $1,000 on property taxes or rent paid. Household income must be $48,110 or less, and applicants can exclude half of their Social Security income when calculating eligibility. The deadline to apply for the 2025 claim year is June 30, 2026.⁸

Disabled Veterans Real Estate Tax Exemption

Veterans with a 100 percent permanent service-connected disability rating, total disability individual unemployability, or service-connected conditions such as blindness or loss of two or more limbs may qualify for a complete property tax exemption on their primary residence. The veteran must have served during a recognized period of war and received an honorable or under-honorable-conditions discharge. Financial need also factors in. As of January 2025, veterans with annual income of $114,637 or less are presumed to qualify, and those above that threshold can still be considered if their monthly expenses exceed their monthly income.⁹

Clean and Green

Agricultural, forest reserve, and open space land of at least ten acres can receive a preferential assessment under Pennsylvania’s Clean and Green program, which values qualifying land by its use rather than its development potential. Properties under ten acres can still qualify for agricultural use if the land generates at least $2,000 annually in farm income.¹⁰ Because Mercer County is reassessing, the application deadline for the 2027 tax year has been extended from the usual June 1 cutoff to October 15, 2026.¹¹

Open your July 2026 notice the day it arrives. Compare the new assessed value to what your property would realistically sell for, gather your evidence, and if the numbers don’t line up, get the appeal on file well before October 31.

1
Mercer County. Frequently Asked Questions Regarding the Notice of Tentative Assessment Change Letter
2
Mercer County Pennsylvania. Residential Assessment Appeal Form
3
Mercer County, PA. Mercer County Reassessment Update
4
Pennsylvania General Assembly. Pennsylvania Code Title 53 – Section 8844
5
Mercer County, PA. Mercer County Prothonotary Fee Schedule 2026
6
Mercer County, PA. Tax Assessment
7
Pennsylvania DCED. Property Tax Relief Through Homestead Exclusion
8
Commonwealth of Pennsylvania. Property Tax/Rent Rebate Program
9
Commonwealth of Pennsylvania. Real Estate Tax Exemption
10
Commonwealth of Pennsylvania. Clean and Green
11
Mercer County, PA. Clean and Green Valuation Application