San Francisco’s office sublease market has surged 140% since 2020, according to new data from Savills.

The surge follows a wave of office vacations that began with remote work and the pandemic and has more recently stemmed from tech layoffs and turmoil in the broader commercial real estate industry.

Available sublease space in San Francisco reached 8.9M SF in the first quarter, according to Trepp, which reported the Savills data this week. That is up from 3.7M SF in the first quarter of 2020, when the pandemic reached the U.S.

The latest figure is also a 15.6% increase over last year, highlighting the changes that have occurred since interest rate increases began exerting their influence on property markets and inflation impacted employment decisions.

San Francisco’s overall office availability rate was 32.7% at the end of the first quarter, and based on that figure and the amount of sublease space, Trepp concluded that 28.3M SF of office is either vacant or available for sublease in the market.

Thousands have been laid off from the tech juggernauts that made San Francisco the hottest office market in the country in the late 2010s, with companies like Meta, Twitter and Google dismissing workers in droves.

Those layoffs, combined with the continued prevalence of remote work, have led to high-profile subleases, like Uber last month marketing a Mission Bay property it never occupied and Salesforce leaving its namesake tower at 350 Mission St.

Although some companies have gotten tougher on bringing employees back to the office, Bay Area offices are still the least used in the country, according to Kastle Systems’ Back to Work Barometer. For the week ending June 26, Kastle reported office usage in the San Francisco metro area at 44.4% of pre-pandemic levels, the lowest of the 10 cities studied.

With reduced usage and stalled capital markets that make property trades difficult and expensive to execute, office valuations in San Francisco and beyond are falling, and many property owners are struggling to keep up with their loan payments. In February, Columbia Property Trust defaulted on a $1.7B loan tied to seven office buildings, including two in San Francisco: 201 and 650 California St. And in April, WeWork Capital Advisors and Rhone Group defaulted on a $240M note for the office building at 600 California St.

More defaults are likely coming, with a reported $2B in loans on San Francisco buildings due to mature this year, the San Francisco Business Times reported, citing Trepp data.

Trepp’s most recent watchlist for offices in San Francisco includes 444 Spear St., 604 Mission St. and 38 Keyes Ave. They were current on their loans as of Tuesday, according to Trepp, but lease expirations are drawing near, which could hinder their owners’ ability to continue making payments.