Property owners throughout Northwest Philadelphia can expect higher tax bills come December, including in Chestnut Hill, where nearly 90% are seeing increases, according to the city.

The median change in Chestnut Hill was $69,000, according to the Philadelphia Office of Property Assessment (OPA). The median change in assessed value was about $32,000 in both Roxborough and Manayunk. The city mailed its property assessment notices in June.

“Chestnut Hill’s been hit a lot this year. Mt. Airy got hit last year or the year before,” said Janice Manzi, a real estate agent at Elfant Wissahickon, who has lived in Chestnut Hill for about 45 years. “I’m sure people are up in arms about it.”

A property’s assessed value is used to calculate property taxes, so higher assessments lead to higher tax bills. Philadelphia’s current property tax rate is 1.3998% of assessed value, with taxes due in March 2027. The bills are mailed to property owners at the end of the year.

The OPA told the Local over email that it does not consider zip codes or neighborhood boundaries when assessing property values. Instead, it divides Philadelphia into 17 zones containing more than 600 Geographic Market Areas (GMAs), where similar properties sell for similar prices.

For example, Chestnut Hill, which falls under zone U, spans several GMAs. Parts of Mt. Airy fall between zones U and M and include varying GMAs. The city analyzes sales within these smaller GMAs, rather than by neighborhood boundaries, when valuing properties.

According to the OPA’s website, it determines property values based on a property’s size and age, its location, proximity to amenities, and recent sales in the area.

“There have been extraordinary sales in Chestnut Hill in the last five years. But this year in particular, it’s been kind of crazy numbers,” Manzi said.

Because of these sales, she said, it’s unsurprising that property values have gone up.

A Philadelphia Inquirer analysis of recent property assessments found that median assessments rose 8.7% in Chestnut Hill, with even higher percentage increases of 11.2% in Manayunk and 9.7% in Roxborough. Assessments in Mt. Airy and Germantown rose much less overall.

In parts of Manayunk and Roxborough, Manzi said prices have appreciated even more, which could explain the higher property assessments. This spring, she sold three houses in Manayunk for more than their listings.

“Prices have just gone up,” she said.

Manzi says Northwest Philadelphia’s popularity can be attributed to its proximity to Wissahickon Park. “It’s an extraordinary resource. I think that’s a huge appeal to people,” she said.

Another reason for the increased value of Chestnut Hill houses is the low supply, she said. Currently, only 28 houses are on the market in Chestnut Hill.

“The inventory is so small, and it has been tight for the last few years, that people will pay over asking just to get a house,” Manzi said. She added that recently renovated homes will likely see an increase in value.

In an emailed statement, Councilwoman Cindy Bass’s office said that it has received numerous comments from Northwest Philadelphia residents about the property assessments.

“Many homeowners have expressed concern about the financial impact that higher assessments may have on their household budgets,” Bass’s office told the Local. “To further support residents, Councilwoman Bass is planning to host a property tax town hall in August, where homeowners will have the opportunity to hear directly from OPA and the Revenue Department to learn more about the reassessment process, available tax relief programs, and the appeals process, and have their questions answered.”

The assessments have also been discussed widely on social media. On Nextdoor, an East Mt. Airy resident wrote, “My valuation for my house increased by $100,700 and I’m appealing — out of 42 houses on my block that I checked, mine was the third highest increase. I hired a certified appraiser who appraised my house much lower and I’m waiting to hear.”

Homeowners who believe their property value is incorrect can appeal but must prove that their assessed value is incorrect. A first-level review form, enclosed in the OPA’s letter sent to property owners, is due Sept. 1, 2026. Another option is to file a formal appeal with the Board of Revision of Taxes, due Oct. 5, 2026. This form is available online. Property owners can choose to file either or both.

If a property is a primary residence, owners can apply for the Homestead Exemption. According to the OPA’s website, this tax exemption “reduces the taxable portion of your property’s assessed value.” Property owners can apply online, by mail or by phone. The deadline to apply for the Homestead Exemption is Dec. 1.

More information about assessments, appeals and tax relief programs is available on the Office of Property Assessment website, phila.gov/departments/office-of-property-assessment.