In Tredyffrin and Easttown, what happens to a tax bill in the two years after a sale is written into school district policy. The Tredyffrin/Easttown School District's Regulation 3295 tells its business manager to go through county sales records. It flags every taxable parcel that sold in the two fiscal years before the appeal deadline for a price at least 20% above the market value implied by its existing assessment. The board adopted a revised version of the policy 9-0 at its May 26, 2026 meeting.
That rule tells a buyer more about the cost of a Wayne address than the millage rate does. "Wayne, PA 19087" covers parts of Radnor Township in Delaware County, Tredyffrin and Easttown in Chester County, and Upper Merion in Montgomery County. On paper their tax rates look far apart. Correct for how each county assesses property, and the annual gap mostly closes. The differences that hold up are at the point of sale.
The Millage Gap That Mostly Disappears
Start with the headline figures. In Radnor Township, the 2026 township rate is 2.7101 mills and the county rate is 4.6104, according to Radnor's 2026 Board Approved Budget. Radnor Township School District lists 16.3263 mills for the 2026-27 tax year. In Tredyffrin, the township's tax page lists 4.313 township mills for 2026, 5.164 for Chester County, and 31.1364 for the Tredyffrin-Easttown School District in FY 2026-27.
That puts Radnor at about 23.6 combined mills and Tredyffrin at about 40.6. A buyer comparing two listings could fairly assume the Chester County side costs far more to own.
That assumption ignores what a mill is charged against. Chester County's last reassessment was in 1996-97. Since then, most assessments have changed only through an appeal or after permitted work that prompted the county to reassess. Pennsylvania measures that drift with a common level ratio, published as a "factor" that is the reciprocal of the countywide ratio of assessed value to market value. For documents accepted from July 1, 2026 through June 30, 2027, the Pennsylvania Bulletin lists Chester County at 3.27 and Delaware County at 1.83. Montgomery County's Recorder of Deeds lists 3.36 effective July 1, 2026.
Apply those factors and the comparison looks like this, using county-average ratios for 2026-27:
| Radnor Township | Tredyffrin Township | Upper Merion Township | |
|---|---|---|---|
| County | Delaware | Chester | Montgomery |
| Combined millage | 23.6468 | 40.6134 | 35.271 |
| CLR factor, 7/1/2026 to 6/30/2027 | 1.83 | 3.27 | 3.36 |
| Implied assessment-to-market ratio | about 54.6% | about 30.6% | about 29.8% |
| Rough annual tax per $1 million of market value | about $12,900 | about $12,400 | about $10,500 |
| Total realty transfer tax | 2.5% | 2.5% | 2% |
The Upper Merion millage comes from the township's adopted 2026 budget. That budget lists 5.619 township mills, 5.642 county mills and 24.010 school mills, and it labels the county and school figures as based on 2025 rates. The Upper Merion Area School District's 2026-27 rate isn't reflected there, so that column shows direction, not a confirmed current bill.
These are averages. A county ratio describes the whole county, and in a base-year system, individual homes drift away from it at very different rates. That drift is exactly what the school district appeal process is built to catch.
Delaware County's Reassessment Is Already Aging
Radnor's lower millage comes from a 2021 countywide reassessment, and the rate history shows how quickly that reset fades. Radnor Township School District's rate fell from 25.5659 mills in 2020-21 to 13.9224 in the reassessment year. It then rose every year after: 14.2371, 14.6329, 15.2109, 15.7965, and now 16.3263.
The state's factor for Delaware County moved the same way. It was 1.00 for 2021-22, then 1.37, 1.52, 1.63, 1.74, and 1.83 for 2026-27. Five years after assessments were reset to market value, the average Delaware County assessment is back to roughly 55% of market. Delaware County's own transfer-tax page still shows 1.74, which was the 2025-26 figure.
Both sides of the line have also raised rates this year. Radnor's school board approved a 3.36% increase for 2026-27, Main Line Media News reported. Delaware County Council adopted a 4.609-mill county rate on December 10, 2025. The county described it as a 19% revenue increase and estimated it would add about $185 a year for the average homeowner. T/E's budget, adopted June 8, 2026, added 1.4797 mills. The district estimated about $388 more a year for the average assessed T/E home. Neither side is standing still, and the year-to-year changes are small next to the costs that show up at closing.
Where the Transaction Costs Split
The first split is the deed. Tredyffrin's Finance page lists the realty transfer tax as 1% to the township, 0.5% to the Tredyffrin-Easttown School District and 1% to the Commonwealth, for a 2.5% total. Radnor also comes to 2.5%. Delaware County's Recorder of Deeds lists Radnor's local share at 1.5%, an exception to the county's standard 1%. Upper Merion's 2026 budget describes a 1% local tax shared evenly with the school district. Add the state's 1% and the total is 2%. On a $1.5 million sale, 2.5% comes to $37,500 and 2% comes to $30,000. That $7,500 gap depends only on which side of the township line the parcel sits.
The second split comes later. T/E's Regulation 3295 sets out a three-step process:
- The business manager lists every taxable parcel sold in the two fiscal years before the appeal deadline where the sale price exceeds the implied market value by at least 20%.
- With the district's tax appeal counsel, the business manager narrows that list to parcels where a successful appeal would raise district revenue by more than $10,000 in the first year and the appeal pays for itself.
- Parcels that meet both criteria are selected and filed with the Chester County Board of Assessment before the deadline.
Chester County's assessment FAQ puts the annual appeal window at May 1 through August 1, with the decision applying to the following tax year.
The $10,000 threshold is where the math gets specific. At 31.1364 school mills, the district gains $10,000 a year only if the assessment rises by about $321,000. At Chester County's 3.27 factor, that is roughly $1.05 million of gap between the price paid and the value implied by the old assessment. Take a home carrying a $300,000 assessment, which implies about $981,000 of market value. A sale at $2.1 million would put it a little over the line. A sale at $1.2 million would clear the 20% screen but fall far short of the revenue test.
That is arithmetic, not a forecast for any particular house. The 20% sales screen is only the first filter. Under the regulation, a parcel is selected and filed only if it also passes the revenue and cost-benefit tests. Even so, the regulation shows that on the T/E side, the price paid is a public number with a written process attached to it, and the process bites hardest at the top of the market.
What the Courts Settled in 2026
Two rulings this year define how far that process can go. On March 17, 2026, the Commonwealth Court affirmed that Upper Merion Area School District's historical appeal policy violated Pennsylvania's Uniformity Clause. The district had filed 82 appeals, all commercial or industrial and none against single-family homes. The trial court found the policy had been designed to exclude single-family residential properties, and it normally skipped any property assessed at $500,000 or less. The ruling addresses that past practice. The district's current approach isn't established in the record we reviewed.
Two months later, on May 19, 2026, the Pennsylvania Supreme Court decided Downingtown Area School District v. Chester County Board of Assessment Appeals, a Chester County case. The four-justice majority held that "the use of a monetary threshold, without more, does not violate the Uniformity Clause." It also held that a district doesn't have to appeal every parcel above its threshold. Selecting parcels by property type, use, neighborhood or owner residency remains prohibited. Three justices dissented.
One question is still open, and it matters for policies like T/E's. In a footnote, the majority said its opinion does not address whether "recently sold" is a prohibited subclass. It recalled that in a 2023 case, three justices had objected to a policy that considered only recently purchased properties. Monetary thresholds now have firmer footing, while the legal status of sale-triggered screening remains unsettled.
FAQ
Does a lower millage rate mean lower taxes in Wayne? Not on its own terms. Millage is applied to assessed value, and each county's assessments sit at a different share of market value. Using 2026-27 county-average ratios, Radnor and Tredyffrin come out within a few hundred dollars per $1 million of market value.
Is Easttown's transfer tax the same as Tredyffrin's? We couldn't confirm Easttown's current all-in rate from official sources. Easttown shares the Tredyffrin-Easttown School District and Chester County's 1996-97 assessment base with Tredyffrin.
Does Radnor Township School District appeal assessments after sales? We couldn't find a published Radnor policy or appeal resolution either way, so this post makes no claim about Radnor's practice.
When does a T/E appeal affect a tax bill? Chester County accepts annual appeals from May 1 through August 1. A decision applies to the following tax year.
The Sivel Group runs the transfer tax, the county factor and the appeal math on every Wayne property our clients consider, before an offer goes in. Sell smarter. Buy smarter. Move smarter.
This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.
