Why Did a Pennsylvania School Property Tax Bill Go Up Without a Reassessment?

A Pennsylvania school property tax bill can rise even when a home’s assessed value never changes.

When that happens, the school board raised its millage rate, the multiplier every county applies to that fixed assessed value.

Trib Total Media reports that twelve of Westmoreland County’s 16 school districts raised taxes for the 2025-26 school year, with assessments still frozen at a 1972 base year.

Note: This is general information, not legal or tax advice. Millage rates, exclusion amounts, and assessment schedules are subject to change, so confirm the current details with your county assessment office.

How Millage and Assessed Value Combine

Pennsylvania school taxes run on a simple formula.

Assessed value gets multiplied by the millage rate, then divided by 1,000.

One mill equals one dollar of tax for every $1,000 of assessed value, not market value.

That distinction matters.

A home can be worth $300,000 on the market and still carry an assessed value of $30,000.

Pennsylvania counties assess at whatever percentage of market value they last set, often decades ago.

Hempfield Area School District, in Westmoreland County, adopted a real estate tax rate of 95.11 mills for the 2025-26 school year, up from 90.76 mills the year before, according to budget filings the district submits to the state education department.

The district’s taxable assessed value barely moved between those two years.

No reassessment happened.

The district’s tax-rate paperwork even labels the formula it used as the one that applies “if no reassessment.”

That’s a built-in admission that a millage increase and a reassessment are two separate events.

Why the Assessed Value Doesn’t Move

Pennsylvania leaves the property reassessment schedule up to each county, and most counties never set one.

Pennsylvania is the only state in the country that doesn’t require counties to reassess property on a regular schedule, according to Trib Total Media.

Some counties go generations between reassessments.

Westmoreland County still calculates assessed values from a 1972 base year.

Butler County hasn’t reassessed since 1969.

Armstrong County last reassessed in 1997.

Allegheny County reassessed most recently, in 2012, and a judge’s order now requires the county to begin a new reassessment by 2027 and complete it by 2032.

That puts Allegheny among the more current counties in the region rather than the norm.

A reassessment isn’t automatically a tax hike, either.

State law requires a taxing body to lower its millage rate right after a countywide reassessment.

That keeps the change revenue-neutral overall, even though individual bills can still shift up or down depending on how a home’s value moved relative to its neighbors.

Delaware County went through a reassessment for the 2021 tax year, and board members there still describe the result as a mixed bag rather than a straightforward win for homeowners.

So a county without a recent reassessment isn’t sparing homeowners anything.

Not one dollar.

It’s just leaving the assessed-value side of the formula frozen while the millage side keeps moving on its own.

What the Act 1 Index Lets Districts Raise

School boards can't raise millage by any amount they like without a vote.

The Act 1 index caps how far a district can go on its own authority.

The state education department sets a statewide base index every year.

It averages the change in the statewide average weekly wage against a federal employment cost index for schools.

The base index for the 2026-27 school year is 3.5%, down from 4.0% the year before.

That's the floor calculation.

Lower-wealth districts get an adjusted index above the base number, so a district's ceiling depends on its finances, not just the statewide figure.

Hempfield Area's adjusted index for 2025-26 came out to 4.8%, and its board raised millage by exactly that much, landing just under the maximum its index allowed.

Norwin School District sits mostly in Westmoreland County, with a small slice in Allegheny County.

Norwin raised its Westmoreland millage from 91.63 to 96.30 for 2025-26, a 5.1% increase that matched its adjusted index down to a tenth of a point.

Neither board needed a voter referendum.

Staying inside the index is the entire point of the Act 1 system.

It lets a school board raise real estate taxes for operating costs every year, on the same assessed values, with no reassessment and no ballot question in sight.

When Districts Can Exceed the Index

Pennsylvania school boards do have a path past the Act 1 index, and it still has nothing to do with reassessment.

A district that wants to raise millage above its index needs either voter approval at a referendum or an exception granted by the state.

Referendums are rare.

Under Act 25 of 2011, districts can seek an exception for cost increases they don't control.

Those categories cover growth in the local share of special education costs, an increase in the required pension contribution rate, and payments on existing debt.

That's according to a questions-and-answers guide from the Pennsylvania State Education Association.

That's four exceptions in total, counting the two separate debt categories.

The state education department approves every one of them itself, with no court in the loop anymore.

The Pennsylvania State Education Association's Act 1 guide says almost every district that applies for an exception gets it.

Getting an exception doesn't force a district to use it, though.

The same guide puts that share at a little less than two-thirds of approved districts, with the rest adopting a smaller increase anyway.

Freeport Area School District spans Armstrong and Butler counties.

It raised millage close to 5% on both sides of the county line for 2025-26 while covering debt on a $55 million high school renovation.

It did that within its Act 1 index, no exception or referendum needed.

A major building project can drive a tax increase without ever forcing a district past its ceiling.

The Homestead Exclusion's Yearly Swing

Pennsylvania homeowners can lose part of their school tax break even when nothing about their house or their millage rate changes at all.

The homestead and farmstead exclusion isn't a fixed discount.

It's funded by casino gaming revenue the state distributes to school districts under Act 1 of 2006.

The Commonwealth's Budget Secretary certified $1.025 billion in statewide relief for the 2026-27 school year.

That statewide total shifts from one year to the next as gaming revenue shifts.

Every single year.

Each district divides its slice of that money by its number of approved homestead and farmstead properties.

That's why the per-home dollar amount looks nothing alike from one district to the next.

Hempfield Area's exclusion knocked $1,765 off a homestead's assessed value for 2025-26.

Norwin's Westmoreland homes got $1,721.50 the same year.

Freeport Area's Armstrong County homes received $5,437 for 2025-26.

Its Butler County homes, in that same district, got just $1,904 because Armstrong has far fewer approved homesteads splitting a similar pot of money.

A district's allocation can shrink from one year to the next even while its budget and its enrollment hold steady.

When that happens, a taxable assessed value effectively rises even though the millage rate and the county's assessment sat completely still.

The homeowner's net bill rises for a reason that never shows up as a rate change on the tax notice.

What Your Tax Bill Shows

A Pennsylvania school tax bill carries the real estate mill rate printed right on it.

That number is the fastest way to tell what happened.

Compare this year's mill rate against last year's.

If the mills went up and the assessed value on the same bill didn't, the millage increase is the whole story.

That holds whether the increase landed inside the district's Act 1 index or above it through an approved exception.

Every Pennsylvania district's real estate tax rate report and its homestead exclusion figures are public.

They're filed with the state education department every year as part of each district's general fund budget.

A district's business office will pull the current numbers for anyone who asks.

Public record.

Checking the exclusion line matters just as much as checking the mills.

A homeowner who assumes a stable exclusion from year to year can miss the reason a bill rose.

That gaming-funded number resets on its own schedule, tied to casino revenue rather than to anything a county assessor decides.

Homeowners 65 and older, plus some younger residents with disabilities, may also qualify for a separate state rebate that has nothing to do with a district's millage or exclusion math.

FAQ

Quick answers to what Pennsylvania homeowners ask most about a rising school tax bill.

Why did my Pennsylvania school tax bill go up if my home wasn't reassessed?

Your school board most likely raised its millage rate within its Act 1 index, or your district's homestead exclusion shrank. Assessed value and millage are separate numbers, and only one of them needs to move for a bill to rise.

What is the Act 1 index for Pennsylvania school districts?

It's the maximum percentage a district can raise real estate millage without voter approval, recalculated every year. The statewide base index is 3.5% for 2026-27, though lower-wealth districts get an adjusted index that runs higher.

Can a school district raise taxes above the Act 1 index without a vote?

Yes, with an exception approved by the state education department. Current law allows four exceptions: Two forms of debt, rising special education costs, and higher required pension contributions.

Why do some Pennsylvania counties go decades without a reassessment?

Pennsylvania is the only state that doesn't require counties to reassess on a set schedule, so the decision is left up to each county. Westmoreland County still uses a 1972 base year, and Butler County hasn't reassessed since 1969.

Does the Pennsylvania homestead exclusion change every year?

Yes. It's funded by casino gaming revenue that the state reallocates to districts annually. Each district recalculates its per-home dollar amount based on that year's allocation and its number of approved homesteads.