Southlake's median single-family sale price in September 2026 was $1,725,000, about 44% above September 2025's $1,200,000. Neither number is a good guide to what a specific Southlake house is worth this fall. Only 36 homes closed in the city that month, which was double the year before, and the jump in the median appears to reflect which 36 homes they were far more than any change in what Southlake homes are worth.

That matters for anyone deciding between Southlake and a neighboring city, and for any owner who saw the headline and started doing math on their own house. A citywide median is the price of the house in the middle of that month's closings. When a month has 18 or 36 closings, one cluster of large estates or a slow month for mid-range homes can move it a long way. The same September data does contain a real change, but it isn't in the median.

What September Actually Counted

Here are the September figures for Southlake single-family resales from the North Texas Real Estate Information Systems monthly report, produced by the Texas Real Estate Research Center at Texas A&M and published October 7, 2026:

The median rose about 44%, but median price per square foot rose about 21%. The average price rose about 64%, faster than either. When the average pulls ahead of the median that much, a group of very expensive sales is lifting the top of the month. The gap between the price increase and the per-square-foot increase points the same way. September's buyers paid more per foot, and the rest of the gap suggests larger homes made up more of the month's closings, though the report does not break sales down by size.

The 18 sales in September 2025 were not unusual. The September 2025 report shows 19 Southlake closings in September 2024, at a median of $1,284,000. A slow September is normal here. What stood out this year was a September with twice the usual count and an average price pulled well above the median.

Nine Months of 2026, Side by Side

If September reflected a real repricing of Southlake homes, the months before it should show a climb. They don't. Here is every 2026 month from the same NTREIS report series:

From January through August, Southlake's monthly median stayed between $1,326,000 and $1,525,000. Median price per square foot stayed in an even tighter band, from $347.57 to $379.46. Then September came in above both ranges.

July and August show that the mix can push the numbers down just as easily. July 2026 had 30 closings against 52 in July 2025, and its median of $1,405,000 was below July 2025's $1,443,750. A reader seeing only July would have concluded Southlake was softening. In August, only 23 homes closed, against 43 a year earlier. August's average price was $1,950,539 while the median was $1,375,000, which points to a handful of large sales at the top of a thin month.

Over July, August and September combined, Southlake closed 89 single-family homes. The same three months of 2025 had 113. One record month followed two slow ones, and taken together, summer and early fall 2026 were quieter than 2025, not hotter.

Colleyville Went the Other Way in the Same Month

The best evidence that Southlake's September median reflects which homes sold comes from the next city over. In the same report, Colleyville's September median fell from $1,000,000 to $800,000, a 20% drop, on 19 closings against 28 a year earlier. Colleyville's median price per square foot rose slightly over the same period, from $270.92 to $275.39.

That's the same metro, the same rate environment and the same month, yet one headline is up 44% and the other is down 20%. In both cities, the median moved much further than the per-square-foot figure. That pattern is consistent with Colleyville's September tilting toward smaller homes and Southlake's toward larger ones, though the report does not list home sizes. Someone comparing the two from headlines alone could decide one city is booming and the other is slipping, when per-foot pricing actually rose in both, by about 2% in Colleyville and about 21% in Southlake. Our Colleyville neighborhood page and Southlake neighborhood page compare the two cities on more than one month of data.

The Change That Will Outlast September

Under the noisy median, September's report holds a steadier signal, and it favors sellers.

Southlake homes sold for 95.2% of list price in September 2026, up from 91.7% a year earlier. Active listings dropped to 115, down from 146 in both June and July and 128 in August. Months of inventory fell from 4.4 in July to 4.0 in August and 3.5 in September. Days on market dropped to 49 from 57 a year earlier. Unlike the median, these measures don't swing much with the size of the homes that close. They track how much room buyers have to negotiate, and that room has gotten smaller since midsummer.

Closed sales also lag decisions. A September closing usually reflects a contract signed weeks earlier, and the August report counted 25 Southlake pending sales. Most of those contracts were signed before the interest-rate change this fall. The Texas Real Estate Research Center's September 2026 Texas Housing Insight reported that mortgage rates moved above 7% ahead of the Federal Reserve's 25-basis-point hike on September 16 and named higher financing costs as the main headwind for housing heading into the fall. September's Southlake numbers mostly describe summer decisions made at summer rates. October and November closings will be the first to show contracts signed after the hike.

The full picture for this fall has two parts. Buyers have less inventory to choose from and less negotiating room than a year ago. Rising borrowing costs could ease some of that pressure later in the season.

Why Southlake's Mix Will Keep Shifting

Southlake will keep producing volatile medians because so few homes change hands and so little gets built. Community Impact's reporting on the area's land shortage found that Grapevine, Colleyville and Southlake are more than 90% built out. Southlake completed 54 new homes in 2024, and new houses in the area are often listed above $2 million. When a city builds a few dozen homes a year, mostly at the top of the market, a few new-construction closings in a given month can push that month's median up.

Several projects in the pipeline could have that effect. Shivers Farm, Trademark Property Company's 40-acre development at SH 114 and North White Chapel Boulevard, broke ground in September. It includes a Whole Foods-anchored commercial district and a residential district of 37 single-family homes. Community Impact reported that Southlake City Council approved a tax increment reinvestment zone for the commercial district on October 6. Earlier in 2026, council approved changes to Jane's Place, a 14-lot project, and Dove Ridge, a seven-home project, according to Community Impact.

Shivers Farm's 37 homes alone would be more than all of Southlake's resale closings in some 2026 months. When those homes start closing, they could move the citywide median because of what sold, whatever happens to the value of existing homes. This is the same kind of mix effect we described in July, when the Carroll ISD boundary changes began sorting values by feeder pattern. Southlake's headline number is made up of small, separate segments, and each one moves for its own reasons.

Three Numbers That Say More About a Southlake House

When the October report comes out in early November, these three measures will tell a buyer or seller more than the median:

1. Median price per square foot, read across several months. Through August 2026 it stayed between $347 and $380. Whether September's $400.63 holds or falls back into that range will show whether pricing actually moved.
2. Sold-to-list ratio. At 95.2% in September versus 91.7% a year earlier, it shows how much negotiating room buyers had. It will be the first measure to show whether higher rates are giving buyers some leverage back.
3. Supply. The drop from 146 active listings at midyear to 115, with months of inventory down to 3.5, is the clearest sign of tighter supply. More fall listings would weaken that signal, and fewer would strengthen it.

For a single home, the most useful comparison is a set of recent sales of similar size, lot and location, adjusted for condition. The citywide median for the month is only a starting point.

If September's headline made you wonder what your own Southlake home would sell for this fall, The Wall Team Realty Associates can give you a figure based on homes like yours, not the citywide median. Start with our instant home valuation, and our team will go through the per-square-foot and sold-to-list numbers for your part of Southlake with you.