Realtor here. Go over here, look up your property, and see the assessment value (Market Value). http://www2.county.allegheny.pa.us/RealEstate/Search.aspx If you don't have documentation from the purchase showing the assessment value at that time, contact the Realtor that sold you the home to discover. It's late 2022, so we're approaching the 7 year holding deadline of torching data, which is upsetting on many levels.

MY guess is that you bought a $400-$450k home that was previously assessed around $100k. Or you bought a $250k that was assessed under $50k w less than 10% down. *I'm ignoring mortgage rates since you stated it was NOT an A.R.M.

Irrespective of my guess, you have research to do regarding Allegheny County property assessments during the last 7 years. It is a valid inquiry to determine that your property was NOT reassessed 18% higher than it should have been. The baseline used was 82% of sales price, and that percentage has been reduced in the last few months to 64%.

It's worth your time to investigate this further. https://www.publicsource.org/allegheny-county-property-tax-appeal-assessment-lawsuit-unbalanced/

Finally, I discovered a friends' property was current on recent years, but delinquent on one year 3 years earlier. Turned out their mortgage company hadn't received notification of re-assessment the year it was performed, or had and it was rejected by intake for whatever reason, and then the subsequent bills were processed properly. At any rate, he was delinquent, but it hadn't reached the profit/loss CBA of being handed off to collections. Sub 200k.

If you don't have the Homestead Exclusion (primary residence only, nationwide in the USA), apply for that as soon as possible.

https://www.alleghenycounty.us/real-estate/abatements-exemptions/act-50/act-50-faqs.aspx

https://www.alleghenycounty.us/real-estate/abatements-exemptions/act-50/act-50-application-process.aspx