Pull up a Ballwin search on any portal and you'll get one number back. One median. One city. But Ballwin runs through two ZIP codes, 63011 and 63021, and lately those two codes have been telling almost opposite stories about what a house is worth. A buyer who anchors to the citywide figure is comping against a blend that doesn't exist on the ground. A seller doing the same is either underpricing a detached home or overpricing a condo, depending on which side of the line they happen to sit.
Here's the split as of August 2026. Realtytrac's ZIP-level figures put the median sales price in 63011 at $449,950, against $376,197 in 63021, a gap of $73,753, or about 20 percent. That gap isn't a fluke of one bad month. Zillow's tracker shows Ballwin's overall average home value at $417,520, up 2.1 percent over the past year, while the 63021 average alone sits at $392,899, up a slower 1.9 percent. For the citywide average to land above what 63021 is doing on its own, 63011 has to be pulling harder in the other direction. It is.
What's actually different between the two ZIPs
The gap isn't about location prestige or school assignment. Ballwin students in both ZIP codes are split across the same two districts, Parkway and Rockwood, depending on the subdivision, not the postal code. The gap is about product mix.
63011 is where Ballwin's detached, subdivision-built single-family stock concentrates: streets like Barham Down, Turnbury Circle, and Aspen Trail, inside subdivisions such as Oak Tree Farm. These are three- and four-bedroom homes on individual lots, the kind of inventory that comps cleanly against itself.
63021 carries a much heavier share of condominium and townhome development: Birnamwood, the Holgate Drive buildings, Crossings Court, Pine Ridge Trails, Tahoe Valley, and Whispering Creek. Plenty of detached homes sit in 63021 too, but the condo share is large enough to drag the ZIP's median down every time a two-bedroom unit closes at $175,000 to $220,000 next to a single-family sale at $400,000-plus.
That's the mechanism. A "63021 median" isn't measuring a worse location. It's measuring whatever ratio of condo-to-house closings happened to clear that month.
| 63011 | 63021 | |
|---|---|---|
| Median sales price (Realtytrac, trailing 12 months) | $449,950 | $376,197 |
| Sale price range | $135,000 to $1,049,000 | $44,520 to $1,650,000 |
| Properties sold, trailing 12 months | 505 | 744 |
| Housing mix | Detached subdivisions | Mixed detached and condo/townhome |
The wider price range in 63021, running from under $50,000 to $1.65 million, is itself a tell. That's not a tight, comparable market. That's condos, patio homes, and large detached lots all reporting into the same ZIP-level number.
The metro trend that's pulling the two ZIPs further apart
This split would matter even in a flat market. It matters more right now because of what's happening across St. Louis County generally. The St. Louis REALTORS monthly housing report tracks residential and townhouse/condo sales separately, and the most recent figures show both categories still gaining in price, but not at the same pace or the same speed of sale. Residential median sales price rose 4.5 percent, while townhouse and condo median sales price rose a slightly softer 4.4 percent. The bigger gap shows up in days on market: residential listings saw days on market climb 8.3 percent, while townhouse and condo listings saw days on market climb 12.5 percent, nearly half again as fast.
Translated to Ballwin, that means condo and townhome inventory in 63021 is taking measurably longer to absorb than detached inventory in 63011, even in a county where both segments are still technically appreciating. A slower absorption rate changes what's actively listed and pending at any given moment, which is exactly the kind of noise that skews a ZIP-level median from month to month. If 63021's condo listings are sitting longer, more of them are stacking up in the "active" column when someone runs a portal search, making the ZIP look softer and slower than the detached homes inside it actually are.
New territory is entering the count too
Ballwin's boundaries themselves shifted this year, which adds another layer to why a single citywide figure needs a second look before you trust it. In January 2026, the Ballwin Board of Aldermen voted unanimously to annex the Arbor Trails and Arbor Crest neighborhoods, along with Oak Brook Elementary School in the Parkway School District, into city limits, effective that April. The petition to annex came from residents in those two neighborhoods, not from the city pushing outward, and more than 75 percent of homeowners in both areas signed on. Those households and their future sales now factor into Ballwin's citywide numbers going forward, which is one more reason to treat any single "Ballwin" figure as a moving target rather than a fixed comp.
What this means if you're pricing a purchase or a listing
If you're shopping in Ballwin and comparing a detached home against a citywide median, you're very likely comparing it against a number that includes a meaningful volume of condo closings pulling the figure down. A $450,000 detached home in 63011 isn't overpriced relative to "Ballwin." It's priced correctly relative to the ZIP where that kind of inventory actually trades.
If you're selling a condo in one of the 63021 communities, the opposite caution applies. Comping against the citywide average risks anchoring your expectations to detached-home appreciation that your unit type isn't currently matching, especially with days on market running longer for that segment right now. A listing agent who prices a Birnamwood or Holgate unit off a blended citywide number is setting up a longer sit on the market than the actual comps for that building support.
The practical fix, whether you're buying or listing, is the same: ask which ZIP and which product type built the number you're looking at before you use it to set a budget or a list price. A median is only useful when you know what's inside it.
FAQ
Is 63021 a worse place to buy than 63011? No. The price gap tracks housing type, not location quality. 63021 includes plenty of detached homes and well-regarded condo communities. The lower median simply reflects a heavier share of condo and townhome sales pulling the ZIP-level average down.
Do both ZIP codes share the same school districts? Ballwin students attend both Parkway and Rockwood schools depending on the specific subdivision, and that assignment cuts across both ZIP codes rather than following the ZIP line.
How current is the 63011 versus 63021 price gap? The figures cited here reflect data pulled in August 2026. ZIP-level medians in a market this size can shift meaningfully month to month based on which properties close, so treat any single snapshot as a starting point for a conversation, not a final number.
Does the Arbor Trails and Arbor Crest annexation affect home values right now? The annexation, effective April 2026, added new households to Ballwin's city limits. It's too recent to have produced a full year of comparable sales data, but it's a factor worth watching as those neighborhoods' transactions begin factoring into citywide figures.
If you're trying to figure out what a specific ZIP code, subdivision, or property type is actually worth in today's Ballwin market, that's a conversation worth having before you write an offer or set a list price. Jeff Lottmann and the team can walk through the real comps for your situation. Schedule a market consultation to get numbers specific to your address, not a citywide average.
