Silicon Valley real estate has changed since early September. At the start of that month the 30-year fixed was under 7 percent and the Fed hadn't moved since its 2025 cuts.
What Changed in Silicon Valley Real Estate in October 2026?
Borrowing got more expensive while buyers gained more homes to choose from, and insurance on the state's plan of last resort went up. Further out, a new townhome law and a Menlo Park housing dispute bear on what gets built here.
The seven stories
How High Are Mortgage Rates in October 2026?
Freddie Mac's weekly survey put the 30-year fixed at 7.40 percent on October 15, unchanged from the week before and up from 6.71 percent on September 3. No week has run higher since November 2023, and a year ago the same survey read 6.27 percent.
The backdrop is the Federal Reserve, which on September 16 raised its target range a quarter point, to 3.75 to 4.00 percent, on a 12 to 0 vote, saying "Inflation remains elevated." The Fed sets the overnight rate between banks, while mortgage rates follow the bond market on their own schedule. The Fed's next decision lands October 28.
What Does 7.40 Percent Do to One Peninsula Loan?
On a $1.74 million loan, 7.40 percent instead of 6.71 adds about $800 a month to principal and interest, and a buyer who holds the September payment can borrow about $117,000 less. The loan is 80 percent of San Mateo County's September median, so the table describes a typical county purchase rather than any one house.
| Loan of $1,740,000, 30-year fixed | 6.71% (Sept 3) | 7.40% (Oct 15) | Difference |
|---|---|---|---|
| Principal and interest, monthly | $11,239 | $12,047 | +$808 |
| Loan an $11,239 payment buys | $1,740,000 | $1,623,297 | about $117,000 less |
Illustration at the Freddie Mac survey rate, 30-year amortization, principal and interest only. A loan this size is a jumbo loan and the survey tracks conforming loans, so get a quote from your lender for your own numbers.
A buyer's first step is a fresh pre-approval at today's rate, written before any offer. How buyers are structuring offers at these rates, including buydowns and seller credits, is in Buying a Home in Silicon Valley When Mortgage Rates Hit 7.4%. For sellers, the buyer who toured in September may come back in October with a smaller budget.
More Homes for Sale in San Mateo and Santa Clara Counties
Both counties added homes for sale faster than they closed them in September. San Mateo County's single-family inventory rose from 424 to 476, up 12.3 percent, and Santa Clara County's from 1,104 to 1,224, up 10.9 percent. Medians rose 4.8 percent in San Mateo County, to $2,175,000, and 1.6 percent in Santa Clara, to $1,880,000.
| Single-family, September 2026 | San Mateo County | August | Santa Clara County | August |
|---|---|---|---|---|
| Median sale price | $2,175,000 | $2,075,000 | $1,880,000 | $1,850,000 |
| Homes for sale | 476 | 424 | 1,224 | 1,104 |
| New listings | 420 | 358 | 943 | 872 |
| Closed sales | 319 | 321 | 726 | 624 |
| Average days on market | 28 | 25 | 27 | 25 |
| Sale price as a share of list | 106% | 107% | 103% | 103% |
Source: SAMCAR and SCCAOR monthly reports via MLSListings, single-family residential, county summary rows, September and August 2026.
A single month does not make a trend, and the rest of the table tempers the inventory story. The average home still closed above its asking price, at 106 percent of list in San Mateo County and 103 percent in Santa Clara. San Mateo County's average days on market moved from 25 to 28, and four Portola Valley sales that averaged 552 days pulled the September figure up.
Every town runs its own numbers. The Silicon Valley relocation guide puts ten towns on one sheet, and the September 2026 market report reads the month town by town.
Buyers now have more to choose from than in the summer, and more time to decide on the homes that sit. Sellers face the other side of the same table, where price and preparation now carry more weight. My read: watch San Mateo County's 420 new listings against its 319 closings, because if that gap holds through October, buyers get more room.
Selling this fall? More listings and a smaller buyer budget both argue for knowing where your home sits before it's listed. My Page One shows a seller that position inside this month's numbers, before anything goes on the MLS.
The FAIR Plan's 29.1 Percent Insurance Increase
Starting October 15, the California FAIR Plan raised its dwelling rates an average of 29.1 percent for new and renewing policies, after asking for 35.8 percent. The FAIR Plan is the state's insurer of last resort, where a home lands when regular carriers won't write it, and that happens more often near the hills and open space.
Per Insurance Business on September 30, State Farm and Allstate remain closed to new homeowners policies in California, while Mercury, Farmers and CSAA are writing statewide. Which carriers will quote a house depends on its address.
A buyer looking near open space should ask about coverage before writing an offer, then get a firm quote during the contingency period, before removing it. If you're selling a home on the FAIR Plan, have the current policy and premium ready, because the buyer's lender will ask.
AB 1751 and Townhomes Without a Public Hearing
On September 29 the governor signed 34 housing bills, and the one to know if you hope to own is AB 1751, the Missing Middle Townhome Ownership Act, effective January 1, 2027. It requires cities to approve qualifying townhome projects without a public hearing: up to three stories and 150 units, with an average home of 1,750 square feet or less, on lots as small as 600 square feet.
The law applies to land zoned for apartments and to vacant lots zoned single-family, and projects of 11 units or more must make at least 10 percent of the homes for lower-income households, or the local inclusionary rate if higher. It leaves out high and very high fire hazard zones, sites covered by SB 79, historic sites and rent-controlled housing, and San Francisco is exempt.
Nothing gets built on January 2, since a project still has to be designed, financed and permitted. Over time, the law opens a path to more for-sale townhomes outside the fire zones. Owners near a multifamily-zoned or vacant lot outside those zones should know it can change what goes up there.
Menlo Park's 39-Story Tower at 80 Willow Road
At 80 Willow Road, the former Sunset Magazine campus, a developer has proposed three towers, the tallest at 39 stories, with 665 apartments, a hotel, office space and a preschool. It was filed under the builder's remedy, a state rule that limits how a city can turn down certain housing projects when its housing plan was out of compliance.
On September 29 the Menlo Park City Council declined to approve it, after the state Attorney General's office wrote to the city in July saying the city changed its reasons. The developer says the council has until October 27 to approve, or the matter goes to court, and on September 30 a council member said a possible buyer for the campus has come forward.
How a court would rule is something I don't predict. For owners near Willow Road the outcome is close to home, and for the rest of the Peninsula it is a test of how state housing law applies to one project on the Menlo Park and Palo Alto line.
The Anthropic IPO and Peninsula Buying Power
On October 13, CNBC reported that Anthropic was showing third-quarter financials to institutional investors ahead of an IPO. Reuters reported a November listing, a date CNBC could not confirm, and on October 14 the SF Standard reported that OpenAI's listing has moved to 2027. Closer to home, the Silicon Valley Business Journal reported in September that Physical Intelligence leased the entire 233,500-square-foot Pear Village building in Mountain View.
The timing matters more than the headline. Employee shares usually sit under a lockup, which Redfin's analysis notes can run up to 180 days, so a November listing would put most of that buying power in 2027. Sellers are better served pricing for the buyers who are here this fall, and buyers can weigh a filing with a date on it above a rumor.
Caltrain's Ridership Year
For the year ending June 2026, Caltrain carried 12.6 million trips, up 37.6 percent, or about 40,800 on an average weekday. Riders scored it 4.4 out of 5 for the second year in a row. Ridership is still about 80 percent of its pre-COVID level, and safety upgrades at all 41 grade crossings are expected by January 2027.
Land near stations is where SB 79 is changing the zoning, which puts the train inside the housing story. For buyers weighing a commute, and owners within a half mile of a station, the SB 79 playbook covers what the new zoning allows there.
Which Dates Matter for Peninsula Buyers and Sellers This Month?
October 27 and 28 come due first: Menlo Park's deadline on 80 Willow Road, then the Fed's decision. AB 1751 follows on January 1, 2027, and Caltrain expects its crossing upgrades by January 2027.
- September 16, 2026The Federal Reserve raises its target range to 3.75 to 4.00 percent, its first increase since the 2025 cuts.
- September 29, 2026The governor signs 34 housing bills, including AB 1751. The same day, the Menlo Park City Council declines to approve the 80 Willow Road towers.
- October 15, 2026Freddie Mac reports 7.40 percent for the second week. The FAIR Plan's 29.1 percent average increase takes effect on new and renewing policies.
- October 22, 2026Freddie Mac's next weekly survey. If the number moved, rerun the loan table above with your lender.
- October 27, 2026Menlo Park. The developer's stated deadline for council approval of 80 Willow Road.
- October 28, 2026The Fed. The rate decision from the October 27 and 28 meeting.
- January 1, 2027AB 1751 takes effect. Caltrain expects safety upgrades at all 41 grade crossings by January 2027.
What this means for you
If you're buying, start with a pre-approval at today's rate and an insurance quote inside your contingency period, then use the added inventory to be choosier about the house and the terms.
If you're selling, you're pricing into more competition and a buyer pool whose budgets shrank in September, so preparation and the first two weeks on market carry the sale.
Either way, if one of these seven changes your timeline, talk with me, and we'll start with the timeline, then the house.
Frequently Asked Questions
What is the mortgage rate in Silicon Valley in October 2026?
Freddie Mac's weekly survey put the national 30-year fixed rate at 7.40 percent on October 15, 2026, up from 6.71 percent in early September and the highest weekly reading since November 2023.
The survey tracks conforming loans, and most Peninsula purchase loans are jumbo loans, so a lender's quote will differ.
Is Silicon Valley a buyer's market in October 2026?
September's numbers do not show one. Homes for sale rose 12.3 percent in San Mateo County and 10.9 percent in Santa Clara County from August to September 2026.
Even so, the average single-family home closed above its asking price, at 106 percent of list in San Mateo County and 103 percent in Santa Clara County.
How much did the California FAIR Plan raise rates and who does it affect?
The California FAIR Plan raised its dwelling rates an average of 29.1 percent for new and renewing policies on or after October 15, 2026, after requesting 35.8 percent.
It covers homes that regular carriers won't write, more often in high fire hazard areas near the hills and open space.
What does AB 1751 do for townhome buyers in California?
From January 1, 2027, AB 1751 requires cities to approve qualifying townhome projects of up to three stories and 150 units without a public hearing, on land zoned for apartments or on vacant lots zoned single-family. Projects of 11 units or more must make at least 10 percent of the homes for lower-income households, or the local inclusionary rate if higher.
High and very high fire hazard zones, SB 79 sites, historic sites and rent-controlled housing are excluded, and San Francisco is exempt. Nothing gets built on January 2, because a project still has to be designed, financed and permitted.
When would an Anthropic IPO affect Peninsula home prices?
Any effect would come after the listing itself, because employee shares usually sit under a lockup, which Redfin's analysis notes can run up to 180 days.
Reuters reported a November listing that CNBC could not confirm. If a listing happens in November, most of that buying power would reach the housing market in 2027.
Sources
- Freddie Mac Primary Mortgage Market Survey, week of October 15, 2026: 7.40 percent, and the September 3 and year-ago readings. Weekly history via FRED, MORTGAGE30US.
- Federal Reserve statement, September 16, 2026: target range 3.75 to 4.00 percent, vote 12 to 0. Meeting dates from the FOMC calendar.
- SAMCAR and SCCAOR monthly market reports via MLSListings, single-family residential, September and August 2026, county summary rows and the Portola Valley city row.
- KQED, California FAIR Plan 29.1 percent rate increase, and Insurance Business, September 30, 2026: effective date, requested 35.8 percent, carrier status.
- Office of the Governor, housing bill signing, September 29, 2026, and the chaptered text of AB 1751.
- Palo Alto Daily Post, September 29, 2026: 80 Willow Road, the council decision, the Attorney General's letter, the October 27 deadline and the possible buyer.
- CNBC, October 13, 2026 and The San Francisco Standard, October 14, 2026: Anthropic IPO preparation, the reported November listing, OpenAI's 2027 timing.
- Silicon Valley Business Journal, September 23, 2026: Physical Intelligence's Pear Village lease, from the headline and subhead of a subscriber article.
- Redfin, July 9, 2026: lockup periods of up to 180 days.
- Caltrain FY2026 ridership report, Mass Transit, October 7, 2026, and the Caltrain board liaison report, October 1, 2026: trips, weekday average, satisfaction, share of pre-COVID ridership, grade crossings.
Market figures are from the SAMCAR and SCCAOR single-family reports for September 2026 and may be revised. Payment figures are illustrations at the Freddie Mac survey rate; get a quote from your lender for your own loan. This article is general information about the market and recent news and is no substitute for legal, tax, insurance or lending advice. Information deemed reliable but not guaranteed. Equal Housing Opportunity.
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