Philadelphia ADU Permit Fees & Cost Calculator
Philadelphia appears to allow accessory dwelling units under city zoning rules, and the main predictable city-level charges are zoning/permit-related fees rather than a dedicated ADU impact fee. The official city permit page lists a $25 filing fee for one- or two-family dwellings, a $1,050 optional accelerated plan review fee, and a $4 per-page record retention fee, while the final permit fee depends on the project and must be verified in the city fee schedule.[8]
Free ADU fee calculator
Estimate local ADU fees
Step 1 of 5: Location
The calculator uses staged city data from the ADUFee database with visible confidence levels and dated source tracking.
Fee overview
The official city result provided does not expose the full building permit fee schedule, so the exact total permit cost for an ADU cannot be confirmed from the available official evidence.
Secondary sources mention flat building permit amounts and the absence of impact/school fees, but these were not confirmed by an official city, county, school district, or state source in the provided results.
ADU legality and fee treatment can depend on zoning district, historic overlays, and whether the project is detached or attached; those details should be verified before using any estimate.
The requested ADU is being treated as a Philadelphia residential accessory unit that would require zoning and building permits.
If the ADU is reviewed under a different permit pathway, the filing fee category may differ from the one-or-two-family dwelling rate.
No separate school district fee or local impact fee was verified from an official Philadelphia source in the provided results.
FAQs
Are Philadelphia ADU fee estimates official?
No. ADUFee.com provides planning estimates only. Final fees are set by the city, utility providers, school district, and other agencies.
What sources are used for Philadelphia?
The database stores city, state, utility, school, county, and other source links where available. Each estimate should still be verified locally.
Can ADU fees vary within Pennsylvania?
Yes. Permit, utility, school, inspection, and impact fees can vary by jurisdiction, parcel, project size, utility provider, and local interpretation.