In the third quarter of 2026, the median single-family sale in Atherton closed at $12,250,000. A year earlier, in Q3 2025, it was $7,760,001. That is a gain of about 58%, according to the San Mateo County Association of Realtors' Q3 2026 report and its Q3 2025 counterpart, both built on MLSListings data.
Most of that jump has more to do with what happened in 2025 than with anything new in 2026. Q3 2025 was the weakest quarter in SAMCAR's Atherton figures from the start of 2025 onward, so any comparison against it looks dramatic. Atherton prices did rise in 2026, though by much less than 58%. The bigger change is the premium buyers now pay over list price. Fewer homes are being offered, and that premium matters more than any median when you are writing an offer.
The Quarter Everyone Is Comparing Against
Here is every Atherton quarter SAMCAR has published since the start of 2025, with the annual 2025 figures at the bottom. Read down the price-per-square-foot column first.
Period | Sales | Median sale price | Median $/sq ft | Avg. home size, sq ft | Avg. % of list received |
|---|---|---|---|---|---|
Q1 2025 | 15 | $8,200,000 | $2,206 | 5,395 | 102% |
Q2 2025 | 23 | $10,280,000 | $2,187 | 5,641 | 103% |
Q3 2025 | 16 | $7,760,001 | $1,754 | 4,956 | 100% |
Q4 2025 | 24 | $11,850,000 | $2,174 | 6,388 | 102% |
Q1 2026 | 12 | $15,709,230 | $2,269 | 7,283 | 102% |
Q2 2026 | 31 | $10,000,000 | $2,200 | 5,485 | 101% |
Q3 2026 | 21 | $12,250,000 | $2,407 | 6,209 | 108% |
2025 annual | 78 | $9,575,000 | $2,159 | 5,683 | 102% |
In every other quarter of 2025, the median price per square foot stayed between $2,174 and $2,206. In Q3 2025 it fell to $1,754. The homes that sold that summer were also the smallest in the series, averaging 4,956 square feet. Few sales, smaller houses and a low per-foot median together made a quarter that sits well outside the rest of the data.
Compare Q3 2026 with the full year 2025 instead and the picture changes. The median price is about 28% above the 2025 annual median of $9,575,000, and the median price per square foot of $2,407 is roughly 11.5% above 2025's $2,159. The Almanac's January through August 2026 tally takes a wider eight-month view of MLSListings data. It puts Atherton's median at $11.3 million, up 17.1% from $9.65 million over the same months of 2025. Every one of these measures shows appreciation. None comes close to 58%.
Twelve Sales Can Move a Median by Millions
The 2026 numbers also swing widely from one quarter to the next. Twelve homes sold in Q1 2026, and their median was $15,709,230. Then 31 homes sold in Q2 2026, the busiest quarter in the table, and the median fell to $10,000,000. That was slightly below the $10,280,000 median of Q2 2025. Measured by its Q2 median, Atherton got a little cheaper in the spring of a year now described as a boom.
Both readings come from the same market. A town with a dozen sales in a quarter cannot produce a stable median. If a few large estates close in a given 90 days, the median rises. If a run of smaller homes on Atherton's older lots closes instead, it falls. The averages show the same effect. In Q3 2026, 21 sales added up to $314,939,000 in volume, for an average of $14,997,095. That is nearly $2.75 million above the median, which shows how much a handful of top-tier closings can pull the figures.
September 2026 shows this even more clearly. Five homes sold that month, at a $13,000,000 median. A single closing would have been enough to change the result.
What Did Change Is the Price of Competing
One column in the table does show a clear shift. Across seven quarters of 2025 and 2026, Atherton sellers received between 100% and 103% of list price on average. In Q3 2026 that figure was 108%. Average days on market fell to 19, from 37 in Q3 2025. Days on market also moves around, since it was 17 in Q2 2025 and 33 in Q2 2026. The 108% has no precedent anywhere in the series.
The Almanac's eight-month data points the same way. From January through August 2026, 19.3% of Atherton single-family sales closed at least $1 million over asking, up from 7.2% in the same period of 2025. Atherton also had 35 sales above $10 million in those eight months, compared with 14 in Palo Alto. A buyer this year is less likely to pay a different price per square foot than a year ago. They are much more likely to pay well above the number on the listing.
This changes the arithmetic of an offer. When sellers receive about 102% of list, the asking price is a reasonable estimate of the closing price. At 108%, and with nearly one sale in five closing seven figures over asking, the list price works more like an opening bid. On an $11 million list, that six-point gap is more than $600,000.
Why Higher Prices Have Not Brought More Listings
Normally, higher prices draw more sellers into the market. Atherton is getting fewer. The Almanac reports 77 new single-family listings in Atherton from January through August 2026, down 10.5% from 86 a year earlier. Sales rose only slightly, to 57 from 55. In Q3 2026, the town had 2.3 months of inventory, compared with 2.4 a year earlier. Supply barely moved even as prices climbed.
The Almanac's reporting gives three reasons, and each one pushes in the same direction.
- New money at the top. The Almanac reports that wealth from AI companies, including recent and expected IPOs, is drawing buyers into the luxury tier. Agents it interviewed describe tech-industry buyers shopping for homes between $12 million and $34 million in Atherton and Los Altos Hills. A Bloomberg report republished by the Los Angeles Times counted five Atherton sales of at least $30 million in 2026 by late July, against six in all of 2025.
- Buyers arriving from two directions. The Almanac describes buyers moving south from San Francisco along with workers returning from places like Seattle as employers tighten office attendance.
- Owners with low mortgage rates. The same reporting puts this fall's fixed mortgage rates at roughly 6% to 7%. It describes longtime owners who bought at around 3.5% hesitating to sell and buy again at today's rates.
More buyers who are less sensitive to rates, competing for fewer homes from owners who are more sensitive to rates, explains the 108% better than any change in what Atherton homes are worth per square foot.
Price per Square Foot Leaves Out the Land
Price per square foot is a weak yardstick in Atherton, because much of the value is in the land. The Almanac reports buyers spending $10 million to $11 million "for dirt," planning to tear down or heavily remodel the existing house. Its example is a one-acre property on Fairview Avenue that, according to the September 2026 article, sold the previous November for $10.7 million, against a $7.8 million asking price. The property included a house but was marketed as a redevelopment opportunity.
When a buyer is mainly paying for the acre, the per-foot price says little about the house. A dated 4,000-square-foot home on a flat, buildable acre can show a very high per-foot price and still be what the buyer actually wanted. This is also part of why Q3 2025 looks so low. A quarter dominated by smaller houses on typical lots produces a lower per-foot median.
2026's recorded top-tier sales show the same pattern. Each property is a mix of land, house and location:
- 89 Mandarin Way, $31 million, recorded in The Almanac's April 6 to 24 roundup.
- 89 Mercedes, $30 million, a modern home with fully retractable glass walls, in the Feb. 23 to March 13 window.
- 35 Barry Lane, $23,988,888, a Tuscan-inspired villa in the Circus Club area.
- 241 Polhemus, $22,750,000, a restored Mediterranean Revival.
- 187 James, $12,760,000, in the June 16 to July 10 window.
- 99 Tallwood Court, $12,747,000, in the Aug. 24 to Sept. 11 window.
The Almanac compiles these from county deed records published four to eight weeks after escrow closes. The windows are recording periods, not exact closing dates.
The 108% average also hides sales that went the other way. Mansion Global reported that an Almendral Avenue estate closed at $33.25 million in late July 2026, against an asking price just under $36 million. Even in the most competitive year in this data, a trophy property at the very top can still sell below its ask.
Sales the Data Does Not Capture
Some of Atherton's market never shows up in SAMCAR's tables. The Los Angeles Times, citing Bloomberg, reported that about 24% of Atherton homes sold without a public listing in 2025, up from 21% in 2024. The Almanac's own tables note that homes sold without an MLS listing may not appear in the MLS data. If roughly a quarter of the market trades privately, a 21-sale quarter is an even smaller sample than it looks.
A Few Direct Questions
Did Atherton prices really rise almost 60% in a year? Not on any stable measure. The 58% compares Q3 2026 with an unusually weak Q3 2025. Against the full year 2025, Q3 2026's median price per square foot is up about 11.5%. The Almanac's January through August comparison shows the median up 17.1%.
Which number is most useful when writing an offer? The share of list price sellers are receiving. In Q3 2026 it averaged 108%, the highest of any quarter in SAMCAR's figures since the start of 2025, and 19.3% of sales from January through August closed at least $1 million over asking.
When will the next quarterly figures appear? SAMCAR posted its Q3 2026 release on October 9, 2026, so Q4 figures will likely follow a similar timeline after year-end. Expect them to swing again. Q4 2025's median of $11,850,000 is a much tougher comparison than last summer's.
When you are pricing a bid on an Atherton estate, or a list price that has to survive a 108% market, the quarterly median will not tell you much. Helen & Brad Miller are glad to go through the recent Atherton sales most comparable to a property you are considering, including what each one received against its asking price. Reach Out Today.
