Distribution of Lot Sizes in Hillsborough

Buyers ask me about the usual lot size in Hillsborough more than almost anything else about the town. How big is a normal lot here? How rare is an acre? If land is the priority, which part of town should the search start in?

I usually answer with the median or most common lot size per MLS records. But I thought, why not provide a holistic view to an interested buyer about everything they need to consider before moving in.

My team and I pulled the assessor records for every single-family parcel in Hillsborough, grouped them by size, and placed each one inside its MLS neighborhood. That is 3,900 homes across 14 neighborhoods. Hillsborough is entirely single-family residential, with no condominiums, townhomes, or commercial property inside its borders, so these 3,900 parcels are the whole town.

The picture is tighter than most people expect. The median Hillsborough lot is 23,887 s/f, which is a little over half an acre. 1,534 homes, or 39.3% of the town, are on lots between 20,000 and 24,999 s/f. A standard Hillsborough home would most likely fall in this range.

Key Takeaways

• The median Hillsborough lot is 23,887 s/f, which is roughly 0.55 acres, and the average is 32,240 s/f.

• The most common lot size in Hillsborough is 20,000 to 24,999 s/f, covering 1,534 homes, or 39.3% of the town.

• 1,117 homes, or 28.6% of Hillsborough, are on lots of 30,000 s/f or larger.

• 510 homes, or 13.1% of Hillsborough, are on an acre or more. The count drops to 243 homes at 1.5 acres, 149 homes at 2 acres, and 32 homes at 3 acres.

• Acre-plus lots are concentrated in a few neighborhoods, because Parrott Drive, Hillsborough Knolls, Lakeview and Carolands together hold close to half of them.

• Lots under 10,000 s/f are the rarest category in Hillsborough at just 17 homes, or 0.4% of the town.

• Parrott Drive has the largest lots of any neighborhood, with a median of 50,999 s/f, and Hillsborough Heights has the smallest, at 20,314 s/f.

How big is the typical lot in Hillsborough?

The median Hillsborough lot is 23,887 s/f, and the average is 32,240 s/f. The gap between those two numbers matters, because a small number of very large estate parcels pulls the average up. The median is the better number to consider when you are comparing homes.

Half of all Hillsborough homes fall between 21,799 s/f and 31,890 s/f. Move up to the top 10% and the threshold is 49,040 s/f, or about 1.13 acres.

Hillsborough is often described as a half-acre-minimum town, and the records mostly bear that out, because 81.4% of homes are on 21,000 s/f or more. That leaves 656 homes, or 16.8%, on lots under 20,000 s/f, and they are concentrated in a handful of neighborhoods.

What is the most common lot size in Hillsborough?

Every single-family parcel in Hillsborough, grouped by lot size. The module below shows the count and the share of the town in each band.

How do lot sizes vary across Hillsborough neighborhoods?

Hillsborough has 14 MLS areas or neighborhoods, numbered 440 through 453: Hillsborough Heights, Brewer Subdivision/Upland, Hillsborough Park, Parrott Drive, Tobin Clark Estate, Lakeview, Carolands, Hillsborough Knolls, Homeplace, Country Club Manor, Skyfarm, Hillsborough Hills, Hillsborough Oaks, and Ryan Tract. Every home is placed inside the official MLS area boundary it falls within, and the module below covers all 14 neighborhoods. The module can be read as a table, a heatmap, or a set of bars, and neighborhoods are ordered by median lot size.

Which Hillsborough neighborhoods have the largest lots?

• Parrott Drive has the largest lots in town by a wide margin. The median is 50,999 s/f, and 25 of its 41 homes are on an acre or more. It is also the smallest neighborhood in Hillsborough, so homes there come up for sale rarely.

• Hillsborough Knolls is second at a 32,397 s/f median, and 47 of its 79 homes are 30,000 s/f or larger.

• Skyfarm is the largest of the big-lot neighborhoods at 361 homes. Only 1 home in Skyfarm is under 20,000 s/f, which makes it the most consistently large neighborhood at real scale.

• Lakeview holds more acre-plus parcels than anywhere else in Hillsborough, with 106 of them. Its median is mid-range at 23,511 s/f because it is also the biggest neighborhood at 671 homes, so it contains a wide spread.

Which Hillsborough neighborhoods have the smallest lots?

• Hillsborough Heights has the smallest lots in town, with a median of 20,314 s/f. 143 of its 296 homes are under 20,000 s/f, which is close to half the neighborhood.

• Ryan Tract is next at a 21,766 s/f median, and 66 of its 171 homes fall in the 15,000 to 19,999 s/f band.

• Hillsborough Oaks is third at a 22,100 s/f median, and 94 of its 258 homes are under 20,000 s/f.

Together, Hillsborough Heights, Hillsborough Oaks, and Ryan Tract account for 307 of the 656 Hillsborough homes under 20,000 s/f. Small lots in this town are geographically concentrated, not spread around.

Which Hillsborough neighborhood is the most uniform?

Carolands is the most predictable neighborhood in Hillsborough. 347 of its 548 homes, which is 63%, fall in the single 20,000 to 24,999 s/f band, and only 3 homes in the entire neighborhood are under 20,000 s/f. A buyer looking at Carolands can expect a lot of roughly half an acre with little variation.

Brewer Subdivision/Upland is the opposite. Its 210 homes are spread almost evenly across five of the six bands, so lot size there has to be checked property by property.

Every Hillsborough home mapped by lot size

Below is every single-family home in Hillsborough plotted by lot size. Each color band can be turned on and off in the map legend.

• Number of lots under 10,000 s/f: 13 (blue pushpin)

• Number of lots 10,000 s/f to 14,999 s/f: 88 (yellow pushpin)

• Number of lots 15,000 s/f to 19,999 s/f: 543 (dark red pushpin)

• Number of lots 20,000 s/f to 24,999 s/f: 1,531 (orange pushpin)

• Number of lots 25,000 s/f to 29,999 s/f: 591 (purple pushpin)

• Number of lots 30,000 s/f and above: 1,112 (green pushpin)
  Total lots mapped: 3,878

Hillsborough has 3,900 single-family parcels in all. The 22 not shown on the map have no matching county parcel record.

About this data

Lot sizes come from San Mateo County assessor active-parcel records for all 3,900 single-family parcels in Hillsborough, compiled for Burlingame Properties in 2026. Each parcel was matched to its MLS neighborhood by assessor parcel number and parcel geometry, then tested against the official MLS area boundaries. 44 homes, or 1.1%, could not be matched to a boundary and are counted in the town totals but left out of the neighborhood table. Figures are current as of September 2026 and are reliable but not guaranteed.

Get in Touch

If you are weighing two homes with different lots, wondering whether an acre is realistic in the neighborhood you have your heart set on, or trying to price a property whose lot is unusual for its street, I am happy to walk through the numbers with you. Get in touch and we can look at how your situation compares to the rest of the town.

This article is copyrighted by Raziel Ungar and may not be reproduced or copied without express written permission.