Hillsborough sellers got 106% of list price in July 2026 and again in August. In September they got 98%. A swing like that sounds like a market turning. In a town that closes about a dozen single-family sales a month, it's closer to a coin landing differently. The change that will still be there next spring is somewhere else. Fewer homes are coming to market, and roughly the same number of buyers are closing on them.
That difference matters if you're weighing Hillsborough against Burlingame this fall. The monthly ratio is the number everyone quotes, and it's the least stable number in the report.
Three months that look like three different towns
Here are Hillsborough's single-family figures from the San Mateo County Association of Realtors monthly reports, which draw on MLSListings data. The September report was posted October 9, 2026.
| Hillsborough, 2026 | July | August | September |
|---|---|---|---|
| Homes sold | 9 | 11 | 12 |
| Median sale price | $7,470,000 | $7,600,000 | $6,075,000 |
| Average sale price | $8,169,888 | $14,454,363 | $7,489,156 |
| % of list price received | 106% | 106% | 98% |
| Average days on market | 51 | 33 | 42 |
| Average lot size, sq ft | 43,883 | 75,570 | 33,044 |
Every column rests on nine to twelve closings. With a dozen sales, each one is about a twelfth of the month's result, so two or three estates that took a price cut can pull the whole ratio below asking. July's 106% came from nine homes. A town that size can post a "hot" month and a "soft" month back to back with no change in buyer behavior at all.
The average sale price line shows the problem most plainly.
One closing on Ralston Avenue moved August's average by millions
August's average was almost twice its median. The gap comes from a single property. According to the San Francisco Chronicle, Villa de Verano at 3000 Ralston Avenue closed at $70 million on Thursday, August 6, 2026.
The arithmetic is short:
- Hillsborough's August 2026 sale volume was $158,998,000 across 11 homes.
- Take out the $70 million estate, and $88,998,000 remains across 10 homes.
- That works out to about $8.9 million per home. The headline figure was $14.45 million.
The same estate lifts the third-quarter average too. Q3 2026 volume of $322,396,880 across 32 sales gives an average just over $10 million. Without Villa de Verano, the other 31 sales average about $8.1 million. The estate also helps explain August's 75,570-square-foot average lot. That lot figure leads to the next distortion, which is price per square foot.
Lot sizes changed which homes were counted
In September 2026, Hillsborough's median price per square foot was $1,583. Burlingame's was $1,623. Read quickly, that says a square foot of house cost more in Burlingame than in Hillsborough last month.
Over the full third quarter, the order flips: $1,736 in Hillsborough against $1,583 in Burlingame. Neither town repriced in four weeks. What changed was the set of homes that happened to close. September's Hillsborough sales averaged 33,044 square feet of land, down from 75,570 in August. A Hillsborough price is largely a price for land, and a price-per-square-foot figure divides it by the house alone. When the month's sales lean toward smaller parcels, the per-foot number drops even though nothing about the town has changed.
So the monthly ratio, the average and the per-foot figure all move with the mix of homes that closed. The figures that don't depend on the mix come from comparing a full quarter against the same quarter a year earlier.
What actually changed between 2025 and 2026
| Hillsborough, single-family | Q3 2025 | Q3 2026 |
|---|---|---|
| New listings | 42 | 33 |
| Homes sold | 31 | 32 |
| Homes in inventory | 35 | 21 |
| Months of inventory | 3.4 | 2 |
| Median sale price | $5,125,000 | $6,550,000 |
| % of list price received | 97% | 103% |
Sales barely moved, with 31 closings in Q3 2025 and 32 in Q3 2026. New listings fell from 42 to 33, and inventory fell from 35 homes to 21. Buyer demand held about steady while supply shrank. Under those conditions sellers gain pricing power, and the quarterly sale-to-list ratio rose from below asking to above it.
The September-to-September comparison shows the same thing in a single month. In September 2025, Hillsborough had 21 new listings, 35 homes in inventory, 61 average days on market, and a median of $5,355,000. In September 2026, it had 12 new listings, 21 homes in inventory, 42 days on market, and a median of $6,075,000.
So September 2026's 98% looks like a reversal, but it matches where Hillsborough sat a year earlier, at 97%. The sale-to-list ratio returned to its 2025 level while inventory stayed down by about 40%. Sellers this fall face less competing supply than last fall's sellers did, even though September's ratio looks like last September's.
There's one possible reason the luxury end could stay thin. In The Almanac's September 24, 2026 survey of Midpeninsula agents, a Menlo Park agent said many high-end sellers are holding off until buyers expecting cash from upcoming AI company IPOs can enter the market. That comment covered the Midpeninsula broadly, not Hillsborough specifically. Still, it fits a market where the number of listings, rather than the number of buyers, sets the tone.
Burlingame runs on a different clock
Next door, the same three months look nothing alike. Burlingame sold at 109% of list in July 2026, 107% in August and 109% in September, with average days on market of 13, 11 and 18. July's report shows 0.4 months to sell at that pace. For Q3 2026 as a whole, Burlingame closed 57 homes at a $3,450,000 median and 109% of list, up from 50 sales, a $2,947,500 median and 105% in Q3 2025.
Burlingame's ratio is steady because it rests on more sales and more similar homes. Its September sales averaged 6,102 square feet of land, against 33,044 in Hillsborough. In Burlingame, closing above list has been the norm every month this quarter. In Hillsborough, the price depends heavily on the particular estate and how long it takes to find its buyer. That's why a 42-day average and a below-list month can sit alongside the tightest supply in two years.
For a buyer comparing the two towns, this changes the preparation. Burlingame's figures point to a fast, competitive offer process every month. Hillsborough's point to a market where supply is limited but each sale is negotiated on its own terms. Its monthly averages don't predict how the next estate will sell.
Reading the October report when it lands
Until the October report posts, September is the latest month on record, and the Q3 report is the steadier signal. When the new figures arrive, these lines carry the most information for Hillsborough:
- New listings and inventory. Is inventory still near 21 homes, or climbing back toward 2025's level of 35?
- Number of sales. A dozen closings is a small base for any ratio.
- Average lot size. A large jump or drop means the mix of homes changed, and the average and per-foot figures will move with it.
- Median against average. A wide gap usually means one estate is pulling the average.
Each of those numbers is on the SAMCAR market data page every month, broken out city by city.
If you're deciding whether this fall's thinner Hillsborough inventory works in your favor as a seller, or how to approach an estate that has been listed for six weeks, Comaroto Properties can walk through the specific homes behind the town-wide figures. Request a personalized consultation, and we'll look at the sales and listings that apply to your property or search.
