When Eleanor H., 66, called the Social Security Administration last month seeking details about her retirement benefits, she didn’t expect to comfort the representative who answered. The woman started sobbing.

“I asked her what was wrong, and she said she and her co-workers were informed by email to accept a taxable $20,000 payout or risk termination,” said Eleanor, who lives in New Jersey (she asked to use only her first name out of privacy concerns).

The rep still answered all of Eleanor’s questions. “Through her tears she said, ‘What am I going to do?’”

The Social Security Administration, which sends retirement, survivor and disability payments to 73 million people each month, has long been called the “third rail” of politics — largely untouchable given its widespread popularity and role as one of the country’s remaining safety nets.

But in recent weeks, the Trump administration, led by Elon Musk’s crew of cost cutters at the Department of Government Efficiency, or DOGE, has taken its chain saw to the agency’s operations. The agency has announced plans to cut up to 12 percent of its work force, at a time its staffing is at a 50-year low. It has also offered early retirement and other incentives, including payments up to $25,000, to the entire staff.

Many current and former Social Security officials fear the cuts could create gaping holes in the agency’s infrastructure, destabilizing the program, which keeps millions of people out of poverty and large percentages of retirees rely on for the bulk of their income.

The actions have caused Social Security employees and former commissioners and executives of both parties to sound alarm bells, saying it would be difficult to repair the damage, which could threaten access to benefits.

“Everything they have done so far is breaking the agency’s ability to serve the public,” said Martin O’Malley, the most recent former Social Security commissioner under President Joseph R. Biden Jr. He said he feared that Mr. Musk’s team had taken most of the actions necessary to create a total system collapse, whether in skyrocketing wait times for customer service, system interruptions or a timely payment of benefits.

In a statement to The New York Times, the Social Security Administration said that it was “identifying efficiencies and reducing costs, with a renewed focus on mission critical work,” including streamlining redundant layers of management, and is “committed to ensuring Americans get the help they need.”

Social Security benefits cannot be changed without legislation passed by Congress. But the delivery of those paychecks — and enabling new people to enroll or make changes — rests upon a complex set of systems that are powered using programming languages developed in the 1970s.

The people who can most deftly operate the agency’s old systems are, perhaps not surprisingly, nearing or already eligible for retirement. At least 30 percent of the technical staff in the office of the chief information officer fits in those categories, former executives estimated.

“We are looking at a degradation of the system as a whole because we have a whole line of expertise walking out the door,” said Shelley Washington, executive vice president of the American Federation of Government Employees Local 1923, a unit of the federal workers’ union. “They are firing first and aiming later.”

He said the delivery of checks for people already enrolled in the system shouldn’t be affected, for now — but it’s becoming increasingly uncertain who will be around to quickly fix issues when they arise.

Michael Astrue, a former agency commissioner appointed by President George W. Bush, said it appeared that Mr. Musk has imported the strategy he used when he bought Twitter, “where you go into some place established, level it and then figure you’re going to improvise your way out,” he said, speaking at a briefing on Thursday held by the National Academy of Social Insurance. “It’s extremely destructive.”

Jason Fichtner, who held several positions at the agency, including deputy commissioner and chief economist, put it even more bluntly at the briefing. “It’s more like a drunk operating a wrecking ball,” he said.

The White House issued a statement on Tuesday, reiterating that President Trump would not cut Social Security, Medicare or Medicaid benefits.

Few dispute that the aging technology needs a reboot. The system hasn’t undergone a major overhaul because Congress hasn’t allocated money for it. It’s also an enormous undertaking, and a lack of continuity in leadership makes it difficult to carry out, current and former technology staff and executives said. It would take an estimated five to seven years and cost more than $2 billion, according to one former technology executive, who didn’t want to be named because the analysis had not been completed.

Though experts familiar with the agency’s operations acknowledged there was room to improve efficiency, they said it was already run leanly. The agency functions on a budget of less than 1 percent of its annual benefit payments, which provide retirement, survivor and disability payments.

“This is extremely low,” Mr. O’Malley said, noting that it’s far lower than the administrative costs of private insurers.

Confidentiality concerns

That hasn’t stopped Mr. Musk’s team. Even without a permanent commissioner, the agency is making big decisions: It has already said it would eliminate 7,000 of its 57,000-person work force, and will close six of its 10 regional offices, which coordinate and provide support to employees.

Of its 1,200 field offices that directly serve the public, more than 40 are to be closed, according to Social Security Works, an advocacy group. The group is trying to track the changes, but said that its data was based on an unreliable list released by DOGE. (The Social Security headquarters itself was also on a closings list, then later dropped.)

Two dozen senior staff members have announced their departures, including the agency’s top three cybersecurity executives, according to a memo issued on Feb. 28 from Leland C. Dudek, the Social Security Administration’s acting commissioner. He took the reins when Michelle King, the previous acting commissioner, left abruptly after refusing to give DOGE representatives access to private data.

Tiffany Flick, the agency’s former acting chief of staff with 30 years of service at Social Security, recently recounted the events around that episode, which also led to her retirement. She expressed deep concerns about the safety of the confidential data and the program overall, according to her sworn testimony on March 6 in a federal lawsuit. The data, she said, has already been misinterpreted and used to spread misinformation.

Mike Russo, the new chief information officer, “seemed completely focused on questions from DOGE officials based on the general myth of supposed widespread Social Security fraud, rather than facts,” Ms. Flick said.

The “disregard for critical processes” and the “significant loss of expertise” have left her seriously concerned the programs will not continue to operate without disruption.

“That could result in benefit payments not being paid out or delays in payments,” she said.

Angela Digeronimo, a claims specialist and a union leader in New Jersey who has been with Social Security for 28 years, said she believed she was witnessing a dismantling of the agency.

“It will affect the public in a very tangible way,” she said, speaking in her capacity as a union official, noting that it already takes about eight months for applicants to the disability program to learn if they’re eligible. “I hate to say this, but more and more people will die while waiting for a medical determination on their disability claim.”

Customer service concerns

Nicole Francis, a financial planner in New York, called the agency last month on behalf of a 100-year-old client who wanted to change the bank into which her benefits were deposited. Ms. Francis knew there would be a wait, but she didn’t expect it to be more than two hours.

Instead of holding, she visited her client at home and helped her make the change with a new online account.

“Not all senior Americans have a trusted representative and should have the option of telephone customer service,” she said.

Last week, in an effort to combat fraud, the agency said it would no longer allow beneficiaries to change bank information over the phone — only online or in person.

Mr. Musk has said that he wants to cut waste, fraud and abuse at the agency, but he and President Trump have continued to repeat false claims that millions of dead people are collecting benefits.

In fact, the Social Security Office of the Inspector General, which is charged with uncovering fraud and inefficiencies, published a report in 2023 that explains why these people don’t have recorded deaths, but also do not collect checks.

“Both Musk and Trump are grossly mischaracterizing the death data,” said Kathleen Romig, director of Social Security and disability policy at the Center on Budget and Policy Priorities, and a former agency adviser. (Mr. Trump also fired the acting inspector general.)

Last week, Mr. Musk, who has called Social Security a Ponzi scheme, claimed that programs like it are used to attract illegal immigrants. The agency has said it collects more than $20 billion in payroll taxes annually from unauthorized workers, most of whom never collect benefits.

“Mixing up these allegations of fraud with these partisan attacks, I think, kind of confuses the public,” said Jack Smalligan, a senior fellow at the Urban Institute and a former deputy associate director at the Office of Management and Budget.

The administration’s aggressive cost-cutting has begun to worry retirees like Eleanor H., who reached the distressed Social Security representative.

She said she won’t be able to survive in retirement without her Social Security check, but has become so concerned about the administration’s actions that she called to see how much she would receive if she filed for benefits early, a few months before her full retirement age. Healthy retirees are often advised against claiming early because waiting longer locks in a higher benefit.

The representative assured Eleanor that she thought her retirement benefits would be safe.

“They will be busy coming for us,” she told her.

Susan C. Beachy and Jack Begg contributed research.