The fallout from the recent banking crisis spurred by the collapse of two banks — and concerns about the health of a third — is bubbling up in the market for commercial real estate lending, as borrowers fear that banks will pull back. That could slow down construction activity and increase the likelihood of a recession, analysts and real estate experts said.

Silicon Valley Bank and Signature Bank imploded in the same week. First Republic Bank teetered for days before its shares partly recovered on Tuesday. Both Signature and First Republic are large lenders to builders and managers of office buildings, rental apartments, shopping complexes and other commercial properties.

First Republic has the ninth-largest loan portfolio in that market in the United States, and Signature had the 10th largest before it collapsed, according Trepp, a commercial real estate data firm.

Midsize and regional banks like Signature and First Republic not only provide the bulk of commercial real estate loans to businesses, they are also part of a far bigger market. Banks typically package the loans they make into complex financial products and sell them to investors, allowing the banks to raise more money to make new loans.

That means that a pullback in lending can also alter the behavior of investors. Commercial real estate contributed $2.3 trillion to the nation’s economy last year, according to an industry association. And because the industry hasn’t fully rebounded from the blow dealt by the pandemic, analysts worry about a fresh slowdown.

“It is a perfect storm right now,” said Varuna Bhattacharyya, a real estate lawyer in New York with Bryan Cave Leighton Paisner who mainly represents banks.

“We were already in a place with a much lower rate of originations,” Ms. Bhattacharyya said, referring to new loan applications that banks process. “It’s hard not to feel a bit of panic and anxiety.”

Ms. Bhattacharyya said lenders would become even more cautious about writing loans for any new construction projects other than the highest-profile “trophy deals.”

The fear among borrowers is that banks will become more conservative about lending. And although the panic appears to have mostly stabilized for now, the specter of bank failure could haunt the decisions of regional banks for months.

For much of last year, commercial real estate lending had begun rebounding from the depths of the Covid-19 lockdowns, when new loan applications almost came to a standstill in the fourth quarter of 2020. By comparison, the annual rate of commercial real estate loan origination by dollar volume grew 18 percent in the fourth quarter of 2022, according to Trepp.

Even before the Federal Deposit Insurance Corporation stepped in to take over Silicon Valley and Signature, a noticeable slowdown in lending to the commercial real estate industry had begun in January.

On an annual basis, the rate of commercial real estate loan growth this year had already been cut in half compared with last year, said Matthew Anderson, a managing director at Trepp. He said some of the slowdown was the result of interest rate increases by the Federal Reserve, which were starting to take a bite out of commercial real estate activity.

And lending has probably tapered off further since the collapses of Silicon Valley and Signature, Mr. Anderson said. “How long and deep the impact will be remains to be seen,” he said.

The universe of commercial real estate includes loans for new construction, mortgages and loans specifically for managing multifamily apartment complexes. The so-called securitized products containing loans that banks make are called commercial mortgage-backed securities — a more than $72 billion market last year. But it’s a different story in 2023, with issuance of those bonds down 78 percent from a year ago.

Daniel Klein, president of Klein Enterprises, a commercial real estate management firm based in Maryland, had been talking to several banks recently about a construction loan for a new project. But just the other day, after the banks collapsed, one of the banks suddenly pulled a term sheet for a loan, he said.

Mr. Klein, whose family-owned business manages about 60 shopping centers, offices and apartment buildings, said that the bank had offered no explanation for its decision, and that he did not know if the trouble in the banking sector had been a cause. He said he expected loan terms from lenders to get more onerous in the coming months, as midsize banks get skittish after the Signature and Silicon Valley Bank collapses.

“Banks in general are being more conservative than they were six or nine months ago,” he said. “But we have been pretty fortunate. We have many long standing community banking relationships.”

Regional banks are a critical part of the commercial real estate ecosystem because their bankers invest a lot of time into forging relationships with real estate developers and managers, said Michael E. Lefkowitz, a real estate lawyer with Rosenberg & Estis in New York. Large banks do not tend to provide that kind of “high-level service” to middle-market real estate firms.

Some of the concerns of real estate lenders eased a bit when the F.D.I.C. announced on Sunday that it had sold substantially all of the remaining deposits at Signature Bank to a subsidiary of a peer, New York Community Bancorp, which is also a major commercial real estate lender. The banking regulator took over Signature on March 12 after business customers — including real estate firms and crypto investors — began pulling money out of the bank.

Before its collapse, Signature was one of the biggest commercial real estate lenders in the New York metropolitan area.

In buying some of Signature’s assets, New York Community Bancorp picked up about $34 billion in customer deposits, down from the $88 billion that Signature had before the bank run, an indication of just how many customers fled the bank before regulators stepped in on March 12 to stem the bleeding.

Even with the sale of banking deposits to New York Community Bancorp, there are worries about whether other banks will fill the void left by the collapse of Signature.

New York Community Bancorp acquired about $12.9 billion in loans from Signature, the F.D.I.C. said, but most were business loans to health care companies and not part of Signature’s large commercial real estate portfolio. That means the F.D.I.C. still needs to find a buyer for Signature’s core commercial real estate loan portfolio.

A spokesman for the F.D.I.C. said that the organization “has not characterize the types of loans left behind” and that they would be “disposed at a later date.”

“I think this means that Signature’s commercial real estate portfolio is still up in the air,” Mr. Anderson of Trepp said.

An indicator that Trepp uses to measure the risk of default to loans held by banks on office complexes found that those facing the most distress were in San Francisco — where First Republic is based.

Banks are likely to cut back on lending to preserve capital in order to strengthen their balance sheets in anticipation of further Federal Reserve interest rate increases and renewed calls for regulators to get more aggressive in monitoring risk taking by banks. Any pullback in new lending could affect the start of commercial developments and push the economy closer to a recession.

As bank regulators work to stabilize the financial system, they will also need to keep an eye on banks holding too many commercial real estate loans in their portfolios — something that can create its own set of problems in a slowing economy.

A report late last year by Moody’s Investors Service, the credit rating agency, found that 27 regional banks already had high concentrations of such loans on their balance sheets. The report said the issue could become problematic for banks if the economy fell into a recession.