State Guide

How to Appeal Your Property Taxes in Pennsylvania (2026 Guide)

Published July 11, 2026 · Updated September 11, 2026

If you own a home in Pennsylvania, your county sets an assessed value that drives your tax bill — but unlike most states, that number usually isn't today's market value. Pennsylvania counties assess at a frozen base-year value, and each county turns market value into an assessment through its own ratio. That makes the appeal math a little different here, and it makes knowing your county's deadline especially important.

The Pennsylvania deadline: September 1 (for next year's taxes)

For most Pennsylvania counties, the default annual-appeal deadline is September 1 under 53 Pa.C.S. §8844 — and here's the wrinkle that trips people up: an appeal you file now sets your assessment for the following tax year. A filing by September 1, 2026 (a Tuesday) challenges your 2027 taxes.

Counties can adopt an earlier date, but the statute forbids anything earlier than August 1 (Montgomery County, for example, uses Aug 1). Philadelphia runs on its own regime entirely: appeals to the Board of Revision of Taxes are due the first Monday of October — October 5, 2026 for tax year 2027. Because the date shifts by county, the single most important step is to confirm your own county's exact deadline before you plan around it.

One Philadelphia exception is worth knowing if you are buying. The BRT's own rules carve out a late window for purchasers: if the property is under an Agreement of Sale executed after the first Monday of October and before December 31 of the year preceding the tax year, the purchaser may file within 30 calendar days of the date the agreement was executed — the signing date, not settlement. For tax year 2027 that means an agreement signed between October 5 and December 31, 2026 still carries a live appeal, 30 days from signing. It applies to the buyer, not to an owner who simply missed October.

Allegheny County (Pittsburgh): September 1, and it changed in 2024

Allegheny County sets its own appeal calendar under the County Administrative Code rather than §8844, and it moved recently enough that a lot of advice online is still wrong. County Ordinance 06-24-OR, passed June 4, 2024, replaced the county's long-standing March 31 deadline: tax year 2025 moved to October 1, 2024, and every year after that is September 1 — which now lines up with the statewide default date.

There is a second half most summaries leave out. The ordinance also confined filings to a window rather than leaving them open all year. The county's Annual Appeals page states it plainly for the current cycle: July 1, 2026 through September 1, 2026, for tax year 2027. So an Allegheny owner who goes looking in the spring will find nothing to file — not because they are too late, but because the window has not opened yet. Filing with the Board of Property Assessment Appeals and Review (BPAAR) carries no fee.

If you read March 31 anywhere for Allegheny, it is out of date.

If the Board of Assessment Appeals rules against you, the next rung is an appeal to the Court of Common Pleas within 30 days (42 Pa.C.S. §5571(b)), where the value is heard de novo.

How Pennsylvania assesses your home

Pennsylvania does not assess most homes at 100% of market value. Counties freeze assessments at a base year and rarely reassess, so your assessed figure can be a small slice of what your home would sell for today. The bridge between the two is the Common Level Ratio (CLR) — the ratio of assessed value to current market value — which the State Tax Equalization Board (STEB) publishes for every county each year, effective July 1 (53 Pa.C.S. §8854).

These ratios vary enormously. A long-unreassessed county like Bucks can sit near 6% of market, while Philadelphia (under its AVI system) assesses at essentially 100%. Because your county's CLR can change year to year — and snaps toward 100% the moment a county does a countywide reassessment — you should pull your county's current CLR from the STEB list rather than rely on last year's figure.

There is no cap in Pennsylvania. The base year is a valuation date, not a growth limit, and it does not reset when you buy — "welcome stranger" reassessment on sale is unconstitutional here. The Homestead/ Farmstead exclusion (Act 1 of 2006) is a flat partial exemption, not a cap, so it doesn't change what your appeal contests.

How an appeal actually works here

Your appeal proves your home's current market value with recent comparable sales, then applies your county's ratio: if your assessment implies a higher ratio than the county's Common Level Ratio, your home is over-assessed relative to your neighbors. This is a ratio-based, uniformity argument grounded in Pa. Const. Art. VIII §1 — closer to New Jersey's Chapter 123 remedy than to a simple market-value cut.

Two Pennsylvania cautions. First, this is a backfire state: on your own appeal the Board — and the Court of Common Pleas on de novo review — can raise your value, so file only when your comps clearly support a lower number. Second, school districts can file their own appeals to raise assessments, but Valley Forge Towers v. Upper Merion ASD (163 A.3d 962, Pa. 2017) holds that all property is a single class and bars districts from singling out one property type.

Filing at the county level

Pennsylvania's appeals run through your county Board of Assessment Appeals (the Board of Revision of Taxes in Philadelphia; the Board of Assessment Revision in Monroe and Lebanon; the Revenue Appeals Board in Northampton), and the mechanics — the exact deadline, the petition form, any fee, and whether your county accepts online filings — vary across all 67 counties. We're building out county-specific guides. In the meantime, use PROppeal to pull licensed comparable sales for your address and confirm the filing logistics with your county's office.

Get your case built

You don't need to wait on a county-specific guide to get started. PROppeal pulls licensed comparable sales for your address, recovers your implied market value through your county's current Common Level Ratio, checks it against your assessment the way a Pennsylvania board actually judges it, and gives you a straight answer on whether your assessment is out of line — before your September deadline arrives.

County appeal pages

Each county page gives the deadline, who decides, and where to file, cited to the county's own pages.

Property tax rules and deadlines vary by jurisdiction and can change — verify with your county before relying on this.