Published November 1, 2026 in Market Update

Inventory rose 45.6% in South Lakes Pyramid, but sales slipped 2.1%

The biggest shift in South Lakes Pyramid right now is inventory. The Real Estate Data Aggregator counted 313 homes for sale in the three months ending August 31, 2026. That is up 45.6% from the same period a year before. More competition means a seller can no longer rely on scarcity alone.

Sales did not collapse. The Real Estate Data Aggregator recorded 426 homes sold across the five ZIP codes in the same period, down just 2.1% from a year before. Demand is still there. It is just meeting more supply.

The Northern Virginia Association of REALTORs reported that closed sales across all of Northern Virginia fell 7.5% in September. South Lakes Pyramid, down only 2.1%, held up better than the broader region.

What the ZIP codes show

The five ZIP codes inside South Lakes Pyramid tell different stories. Vienna and Reston do not move together, and the numbers prove it.

Where homes are still moving fast

Vienna's 22181 ZIP code is the tightest market in the pyramid. The Real Estate Data Aggregator shows 1.3 months of supply there, and a median of just 20 days on market. That is 10 days shorter than the same period last year. More than half of homes, 51.4%, sold above list price.

In 22181, the Real Estate Data Aggregator also shows 72.6% of homes went under contract within two weeks of listing. That share rose 23.7 points from a year before. Sellers in that ZIP are still in a strong position if they price correctly.

Where inventory jumped the most

The Reston ZIPs saw the sharpest inventory increases. In 20190, the Real Estate Data Aggregator counted homes for sale up 78% year over year. In 20191, inventory rose 87%. Both ZIPs also saw pending sales fall, down 15.2% in 20190 and up 7.4% in 20191, so the picture is mixed even within Reston.

ZIP 20194 in Reston is a different case. Inventory there rose only 8%. New listings actually fell 10.2%, and months of supply sits at just 1.5. Sellers there face less competition than in 20190 or 20191.

Prices: up in Reston, softer in Vienna

Reston prices moved up. The Real Estate Data Aggregator shows the median sale price in 20190 rose 15.4% to $600,000. In 20194 it rose 12.2% to $795,000. In 20191 it rose 5.7% to $665,000.

Vienna prices dipped. In 22181, the median fell 5.5% to $1,122,500. In 22182 it fell 6.1% to $1,270,256. Those are small moves on large numbers, but sellers there should price with the current data, not last year's peak.

The broader picture

The Northern Virginia Association of REALTORs reported the median sold price across Northern Virginia reached $744,950 in September, up 4.2% from September 2025. Homes spent an average of 28 days on market in September, unchanged from a year before.

The Federal Housing Finance Agency reported U.S. house prices rose 2.4% from August 2025 to August 2026. Month over month, prices rose 0.3% in August, seasonally adjusted. The national trend is still upward, even if local ZIP codes vary.

Mortgage rates are a factor for buyers. Realtor.com reported rates topped 7% in September 2026. That affects how much a buyer can offer, which in turn affects what a seller can expect.

One last thing: the numbers above cover whole ZIP codes. A single street inside 20191 can behave very differently from the ZIP average. Your block's school zoning, commute access and home type all shape what a buyer will pay. The ZIP code tells you the direction. Your address tells you the number.