By Josh McKnight | The McKnight Team
Apartments got slightly bigger across the country last year. In Philadelphia they shrank. New apartments built between 2016 and 2025 average 747 square feet, which is 163 square feet below the national average, according to a RentCafe analysis.
Renting vs buying in Philadelphia used to be a question about monthly cost. Square footage is now part of it. Units currently under construction in the city average 627 square feet.
How Small Philadelphia Apartments Have Gotten
Philadelphia ranks 88th out of the 100 cities with the largest apartment supply when measured by unit size. The report covered buildings with 50 or more units, so this is professionally managed inventory rather than converted rowhomes. The distinction matters, because those buildings are exactly the ones a renter weighs against a purchase.
The decade over decade comparison is the sharper number. New Philadelphia apartments shrank by 104 square feet against apartments built in the previous decade. RentCafe framed that as the loss of a home office, which is close to literal.
Units under construction average 627 square feet, another 120 below the 2016 to 2025 cohort. The direction has not reversed. It has accelerated. Whatever gets delivered in 2028 will be smaller still.
What Shrinking Units Actually Do to Renting vs Buying in Philadelphia
Developers are not shrinking units out of spite. They are shrinking them because construction costs rose and unit count is how a project pencils. Smaller units, more of them, same building envelope.
Set that against what the numbers show right now. The average Philadelphia home value is $234,630, up 0.2% over the past year, and homes go to pending in around 22 days, per Zillow data through July 31, 2026.
Twenty two days is slow by suburban standards and generous by buyer standards. Philadelphia is the one market in this region where a buyer can still think. You get a second showing. You get a night to sleep on it.
Why Space Per Dollar Is the Comparison Nobody Runs
Renters compare rent to rent. Buyers compare price to price. Almost nobody compares square feet to square feet across the two, which is where the Philadelphia math gets interesting.
A 747 square foot new apartment is the current rental product. A rowhome at the typical city value is usually a multiple of that, with a basement, and with the square footage counted differently but real either way. That comparison does not settle the question, because ownership carries a roof, a heater, transfer taxes, and a property tax bill that renting does not. Reasonable people land differently on whether that tradeoff is worth it at any given rent.
What has changed is that the rental product keeps getting smaller while the owned product does not. That single fact reframes renting vs buying in Philadelphia more than any rate move this year. If someone you know has been renting in the city and complaining about space, tell them to run the square foot math before renewing.
What This Means for You
If you are renting and thinking about buying, price the two on the same basis. Take your rent, take a mortgage payment plus taxes and insurance at the price point you are considering, and divide each by usable square feet. The answer surprises most people in a city where values rose 0.2% over a year. If you are selling a rowhome, that comparison is the actual alternative your buyer is weighing, and the space advantage is worth showing rather than assuming. Measure your finished basement, put the number in your listing, and let the buyer run the comparison in their head.
Twenty two days on market means your buyer has time to comparison shop, so the listing that photographs its space well wins the showing. Space is the one advantage a rowhome holds over every new building going up in the city, and it costs nothing to advertise. The Philadelphia market page has current inventory and pace if you want the numbers before you commit in either direction.
Thinking about buying or selling in Philadelphia? Let’s talk.
