Fairfax County Median Prices went up 21% over the first six months of 2026.

Most people would think that means the value of our homes went up 21%. It doesn’t.

There are dozens of markets operating within Fairfax County. That 21% treats all the markets as one.

A buyer looking for a 1,300-square-foot rambler isn't also looking for a 3,500-square-foot colonial. Those are two separate markets. Each one has different buyers, different sellers, different demand, and different supply.

During the first half of the year, homes in the 1,200 to 1,300 square foot segment of the market appreciated at 2.89%. Homes in the 3,000 to 4,000 square foot segment appreciated at 13.46%. The data in the table below was taken directly from the MLS.

But how is it possible that the whole market increased 21% when no size segment increased even close to that much?

That’s the nature of median prices. They’re considered one of the best ways to measure real estate prices, but they must be interpreted.

Here’s why: the median price is the midpoint of all the sales that are being measured. During the first six months of this year, a larger share of sales in the county occurred in higher-priced homes. As the mix of sales shifted upward, the midpoint, median, did too.

But, during the first six months, the midpoint within any segment didn’t move up as much, relative to where it started, as the midpoint for the county as a whole did.

The Signal in the Noise

The countywide statistic is noise when valuing a specific home. The median price for that home's market segment is the signal.