SAN FRANCISCO — Airbnb said Friday more than 1,000 companies have joined its new program allowing business travelers to use the peer-to-peer-lodging service.

The San Francisco-based startup shaking up the hospitality industry said it signed up 500 companies to its “Airbnb for Business” program within 24 hours of launching the program on July 20.

Now, more than 1,000 firms from at least 35 countries have integrated the program into their corporate travel plans, it said.

“The corporate community’s response to our Business Travel program has been staggering and confirms our findings that business travelers increasingly want to redefine the business trip,” said Marc McCabe, who heads the program.

“The average business travel stay on Airbnb is 6.8 days, which shows how customers are looking for a mix of business and leisure, and often adding a weekend to explore a new destination.”

Among the companies joining the program are online storage firm Box, which now allows employees to use Airbnb accommodations, available in more than 190 countries.

Jeff Mannie, controller at Box, said in the statement that his firm was “impressed that Airbnb’s new Business Travel product suite allows you to uncover unique locations for temporary housing, team offsites and conventions where there is an opportunity to build closer working relationships by sharing accommodations in a casual and friendly environment.”

Facebook, Google, Salesforce and Eventbrite are also using Airbnb for corporate travel.

Airbnb allows people to rent a room or an entire home through the platform, offering flexibility to travelers while giving property owners or renters a source of income.

The company was launched in 2008 and now has some 40 million users worldwide. Its valuation based on its latest funding round is some $25.5 billion.

Traditional hotel chains see Airbnb as a rival and accuse it of helping people avoid taxes and of hosting illegal hotels on its website.