Two homes with the same purchase price can have very different property tax bills. Understanding those differences helps you compare your monthly costs and make a more informed decision about where to buy.
Explore how county, municipal, and school district taxes contribute to a home’s annual tax bill. Start with Upper St. Clair, Mt. Lebanon, and Peters Township, then use official resources to research the properties you are considering.
Start with the Property, Not Just the Price
Property taxes depend on a home’s taxable assessed value and the tax rates that apply to its location. The assessed value may differ from the asking price or purchase price. When comparing homes, review the county, municipal, and school district taxes together, along with any applicable exemptions or exclusions. A listing’s current tax figure is a starting point—not a guarantee of what you will pay in future years.
Compare Property Tax Jurisdictions
Each of these communities has county, municipal, and school district property taxes. Upper St. Clair and Mt. Lebanon are in Allegheny County, while Peters Township is in Washington County. Use the official resources below to check the applicable rates, then review the assessment and tax bills for the specific home.
| Taxing authority | Upper St. Clair | Mt. Lebanon | Peters Township |
| County | Allegheny | Allegheny | Washington |
| Municipality | Upper St. Clair Township | Municipality of Mt. Lebanon | Peters Township |
| School District | Upper St. Clair School District | Mt. Lebanon School District | Peters Township School District |
Upper St. Clair tax information
Peters Township tax information
What Is a Property Assessment?
A property assessment is the value the county assigns to your land and buildings for property tax purposes. It is one part of the calculation that determines your tax bill.
Three different values can apply to the same home:
• Purchase price: What you agree to pay for the property.
• Appraised value: An appraiser’s opinion of the property’s value as of a particular date, often prepared for a mortgage lender.
• Assessed value: The value recorded by the county for calculating property taxes, before any applicable exemptions or exclusions.
These amounts do not have to match. A home purchased for $500,000 might have a county assessment of $300,000. That difference alone does not mean the home is overpriced or that its assessment is incorrect.
Why Can the Assessment Be Lower Than the Purchase Price?
Some counties use values tied to an earlier year, known as a base year, rather than updating every assessment to reflect today’s housing market.
Allegheny County, which includes Upper St. Clair and Mt. Lebanon, currently uses a 2012 base year. Its assessment records therefore should not be read as estimates of what homes would sell for today. Peters Township is in Washington County, which maintains its own assessment records.
When comparing homes across county lines, review each property’s assessment together with its applicable tax rates. Comparing assessments alone will not tell you which home has the lower tax bill.
An assessment can change.
In Allegheny County, changes may result from assessment appeals, new construction, additions, corrections to property records, or a countywide reassessment. Before buying, review the property’s current assessment and ask whether any pending appeal or unfinished assessment could affect future taxes. NOTE: In Washington County, specifically Peters Township, we are seeing homes being reassessed at the time of the new buyer closing on the property.

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Sharon St. Clair
Pittsburgh Relocation Specialist
Whether you’re relocating across the country or moving across town, Sharon provides strategic guidance, local expertise, and fiduciary representation to help you move with confidence.
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