The Paycheck Protection Program was the centerpiece of the federal government’s relief efforts to keep millions of small businesses afloat during the coronavirus pandemic. But new data shows what many had suspected all along: The money was shared unevenly, with the biggest sums going to a sliver of the companies in need.

Detailed loan information released by the Small Business Administration late on Tuesday showed that a mere 1 percent of the program’s 5.2 million borrowers — those seeking $1.4 million and above — received more than a quarter of the $523 billion disbursed.

About 600 businesses — including powerful law firms like Boies Schiller Flexner, restaurants like the steakhouse chain started by Ted Turner, as well as the operator of New York’s biggest horse tracks — received the maximum loan amount of $10 million, according to the data. It was the first full accounting of how federal money was spent through the program. Aimed at small companies — generally those with 500 or fewer workers — the program provided forgivable loans to desperate business owners who were faced with widespread shutdowns.

But the program allowed businesses to take enough money to cover only a couple of months’ expenses, and it has come under criticism for its poorly defined rules and a hasty and haphazard rollout that allowed fraudsters to tap into the money, which will take years of litigation to sort out.

The newly released data also includes details of loans made under the Economic Injury Disaster Loan system, a longstanding Small Business Administration program that was vastly expanded to offer relief to businesses affected by the pandemic. Together, the two programs spread more than $700 billion to struggling companies in just a few months.

The loan data was released under an order by Judge James E. Boasberg of the U.S. District Court in Washington, who rejected the S.B.A.’s request to keep the information confidential. Previously released data on the paycheck program contained only ranges for larger loan amounts, and no information about loans under $150,000.

Calling the program “vast in both size and sweep,” Judge Boasberg wrote in a ruling last month that “the weighty public interest in disclosure easily overcomes the far narrower privacy interest of borrowers who collectively received billions of taxpayer dollars in loans.”

With virus case counts rising rapidly and public health experts predicting a dark winter ahead, small businesses remain fearful about their survival. Many have used up their allotted aid, which was intended to cover up to two months of payroll costs and a handful of other expenses. Many owners say they would immediately apply for additional funds if available, but the rules permit only a single loan, and there has been little movement toward breaking a monthslong stalemate in Washington over additional aid.

President-elect Joseph R. Biden Jr. and his economic advisers have urged quick action on additional stimulus measures. A bipartisan group of lawmakers has proposed a stopgap plan to extend lapsed federal unemployment benefits until March — although at a lower rate — and provide $288 billion to help small businesses, restaurants and theaters. Top Democrats in Congress endorsed the proposal as the basis for further negotiations.

The companies that received the maximum $10 million P.P.P. loan include dozens of restaurant chains such as Ted’s Montana Grill, which was started by Mr. Turner; TGI Fridays; P.F. Chang’s; Black Angus Steakhouse; and Legal Sea Foods. They took advantage of an exception the restaurant industry lobbied for to make chains eligible for the aid money. The New York Racing Association, which operates Aqueduct Racetrack, Saratoga Race Course and Belmont Park, the home of the Belmont Stakes, also received the maximum loan.

Prominent law firms like Boies Schiller Flexner, the high-priced firm run by David Boies, and Kasowitz Benson Torres, founded and run by President Trump’s longtime personal lawyer, Marc E. Kasowitz, also collected loans for $10 million. (It was previously known that both firms received large loans, but the exact amount had not been disclosed.)

Boeis Schiller did not respond to a message seeking comment; Mr. Kasowitz’s firm referred to a previous statement saying the loan helped it preserve hundreds of jobs.

Most of the program’s borrowers sought far less: Loans of $150,000 and under accounted for around 87 percent of the loans made through the program, which ended in August, when its congressional authorization expired. But those loans made up less than 30 percent of the total handed out, about $146 billion.

The data shows how federal money flowed to tenants of Mr. Trump’s properties, like 40 Wall Street, a commercial skyscraper in Lower Manhattan. Nearly 100 businesses listing an address in that building collected loans totaling more than $34 million.

The largest loan in the building went to Atane Engineers, a contractor that changed its name in 2018 after a corruption scandal that culminated when two former top executives pleaded guilty to paying bribes for city infrastructure contracts. The company, which pays $2.5 million a year for its rent at 40 Wall, received a $7.6 million loan, which it said supported 235 workers. The firm did not respond to messages seeking comment.

The data also reveals how inconsistently the Small Business Administration disbursed money through the Economic Injury Disaster Loan, a still-running aid effort that offers companies and nonprofits low-interest loans directly from the government. That program is supposed to make loans of up to $2 million, but the S.B.A., concerned that it would run out of money, imposed various caps, none of which were publicly disclosed to borrowers at the time.

Two organizations received loans in early April for more than $500,000, the cap the agency set on the program later that month. The Jewish Community Center in Stamford, Conn., received $900,000 and the CWC Group, a chiropractic clinic in Bellevue, Wash., received $713,900, according to government data.

The low-interest loan, which has to be repaid, was a lifeline for CWC, said Dr. Sean Kim, the owner of the practice, which does business under the name Blue Spring Chiropractic. Its sales have declined by as much as 70 percent in some months since the pandemic began, he said, and the loan helped him retain 16 employees and contractors.

“This is about survival,” Dr. Kim said. “Without it, we would not be sleeping well.” (The Jewish Community Center did not respond to questions about its loan.)

More than 8,000 organizations got loans for $500,000, a limit that was later lowered to $150,000, where it has remained since May. The disaster loan program has distributed 3.6 million loans, totaling $194 billion, since the coronavirus crisis began — far more than the program had given out in its entire 67-year history.

A Small Business Administration spokesman said the agency’s “historically successful Covid relief loan programs have helped millions of small businesses and tens of millions of American workers when they needed it most.”

Lenders collected $18 billion in fees, according to a New York Times analysis of the S.B.A. data. The largest payment went to JPMorgan Chase, which stands to collect just over $1 billion in fees on more than 280,000 loans worth a total of $29 billion. The runner-up is Bank of America, which will earn $947 million in fees on around 343,400 loans worth nearly $26 billion.

Both banks have pledged to donate any profits they earn from the program, but executives from each have told analysts that their expenses were so high that there may not be much, if any, left to give after the loans are settled.

“We have committed that net proceeds from the fees will be dedicated to supporting small businesses and the communities and nonprofits we serve,” Bill Halldin, a Bank of America spokesman, said on Wednesday. JPMorgan declined to comment.

The Paycheck Protection Program was hastily constructed in late March after Congress passed the $2 trillion CARES Act. The Treasury Department, which called most of the shots on the program, released technical guidance to banks just hours before lending began in April, and the terms shifted many times before the program ended in August. The Treasury Department has issued dozens of changes and clarifications to its rules.

The rules initially required businesses to keep nearly all of their employees if they wished to have their loan forgiven, but Congress later softened the requirements to allow many businesses to have their loans eliminated even if they reduced their employee head count. While economists believe the program contributed to job retention in the pandemic’s early months, its effects faded as the money dried up.

An analysis by Gusto, a payroll provider for small companies, found that the chances that workers would lose their job at a company that took a P.P.P. loan increased by 25 percent during the week that the loan’s restrictions on job reductions ended. Gusto estimated that 232,000 jobs may have been eliminated as the restrictions expired.

“Once that requirement ends, the head count falls off a cliff,” said Luke Pardue, an economist at Gusto. “It was designed to be temporary relief, but what we find is that companies really emerged in no better shape. A lot of that is due to the fact that the economy is in no better shape.”

Discussions in Congress about further economic stimulus measures have included calls for a second round of P.P.P. loans, this time more narrowly targeted to the hardest-hit businesses. Nearly $140 billion remained unspent when the program expired in August.

Lenders and borrowers who already got loans are now working through the next messy stage of the program: getting P.P.P. loans eligible to be forgiven paid off by the government. Most borrowers have until at least mid-2021 to file and many are holding off, hoping that Congress or the incoming Biden administration will simplify what can be a confusing and time-consuming application process.

As of Nov. 22, lenders had submitted 595,000 loan forgiveness applications to the S.B.A., representing about 11 percent of the program’s 5.2 million borrowers. The agency said it had made payments to lenders on 367,000 of those loans.