A new study says that a number of large corporations paid little or no U.S. tax on their U.S. income in 1980.

The study, based on reports by the companies themselves to the Securities and Exchange Commission, said such well-known firms as Chase Manhattan Bank, Squibb Corp. and Monsanto Co. paid no taxes on U.S. income despite domestic earnings of $207 million, $78 milllion and $204 million respectively.

In one of the more controversial findings--which was immediately disputed by the firm--the study said the nation's largest company, Exxon, paid a U.S. rate of 1.3 percent on domestic earnings of $2.5 billion.

Another giant corporation, AT&T, paid an 8 percent rate on domestic earnings of $7.7 billion, the study concluded.

The findings, made public yesterday by Tax Analysts, a tax "reform" group based here, were quickly disputed by spokesmen for some of the companies named. U. J. LeGrange, vice president and comptroller of Exxon, for example, contended that by the company's calculations, it paid federal taxes at about a 40 percent rate. LeGrange said Exxon paid $1.76 billion, including $459 million that was deferred, on before-tax U.S. earnings of $3.69 billion.

The study, which was conducted for Tax Analysts by Richard Kaplan, professor of law at the University of Illinois, contended that the oil company had U.S. earnings of $2.5 billion on which it paid a tax of about $33 million. This huge disparity resulted from an accounting assumption by Tax Analysts to credit all accelerated depreciation to taxes on U.S. income, a step that could make Exxon's tax rate on domestic income appear lower than it is.

There has long been a complex dispute about how to calculate the taxes corporations pay. While not passing judgment on Kaplan's specific findings, Seymour Fiekowsky, assistant director of the Treasury's office of tax analysis, said the new study appeared to be "much fairer" than prior ones, particularly those by former Rep. Charles Vanik (D-Ohio), that compared companies' U.S. taxes to their worldwide rather than just their U.S. income.

Fiekowsky cautioned, however, that calculation of effective tax rates is an extremely difficult process and that the study released yesterday would be criticized in some quarters on at least two grounds. One is that it does not count deferred taxes --those a company does not have to pay until some later date, if ever--as taxes levied. The other is that it subtracts from a company's current taxes refunds attributable to past years.

The companies studied were able to reduce their taxes by a number of altogether legal means. A main one was the investment tax credit, which lets a company subtract from its taxes owed part of the cost of most new equipment. Another was the foreign tax credit, which lets companies subtract from their U.S. taxes income taxes paid abroad. The companies did not yet have the benefit of the large further corporate tax cuts Congress voted last summer at the administration's behest.

The Tax Analysts study found major disparities in effective tax rates among competing companies and in different industries. Six different industry groups were examined with the following results:

The average tax rate paid by the 20 largest commercial banks, all but one of which had U.S. profits, was minus 0.9 percent. This was the lowest of all the industries studied. Negative tax liabilities can be used to get refunds for past or future years in which taxes are owed.

The second lowest rates were paid by the nine largest regulated utilities, an average effective rate of 7.9 percent. AT&T was just about average in this group. Commonwealth Edison Co. paid the highest rate of 20.3 percent, and Southern California Edison was low at minus 8 percent.

The highest effective tax rates were paid by the top 10 non-oil industrial firms--27.7 percent on U.S. income. These rates ranged from 40.1 percent paid by Eastman Kodak on $1.49 billion in domestic income to 6.3 percent for Tenneco.

Running about 5 percentage points below the industrial firms were 20 drug companies which, according to the study, paid an average rate on U.S. income of 22.3 percent. These ranged from 45.7 percent, just barely under the statutory maximum of 46 percent, by Bristol Myers, to zero by Squibb.

For the 30 top oil companies, the Tax Analysts study found that the average rate was 21.9 percent. Among the 10 largest, Exxon paid the lowest rate. Conoco paid 9.7 percent, Mobil 12.1. The highest rate found to have been paid by an oil company was for Amerada Hess, 42.5 percent on domestic earnings of $591 million.

The eight largest steel companies were found to have paid a federal tax rate of 14.5 percent on domestic income, ranging from negative rates for Republic and Wheeling Pittsburgh to a 26.8 percent rate paid by Crane Steel.

The calculations of both the current study and past efforts are inherently subject to extensive controversy, as tax reformers contend that the findings are legitimate and point to the need to close tax "loopholes," while others argue that corporate tax rates, because depreciation has not been adjusted for inflation, are already excessive.

Oil companies, for example, point out that when foreign taxes are taken into account, the worldwide rate of taxation for worldwide income reaches as high as 62.8 percent (Phillips Petroleum) or 63.1 percent (Conoco). Critics, however, counter that foreign countries, in an effort to benefit U.S. oil firms, have adjusted their royalty and tax systems to give the firms the maximum possible direct credits against U.S. tax liabilities.

This conflict between reformers and supporters of corporate tax cuts has become increasingly bitter in recent months. The business community received in the 1981 tax bill sharply increased benefits resulting from a new system of calculating depreciation. These cuts have not yet produced the stepped-up investment, however, that proponents claimed would be a part of a major improvement in the nation's economy resulting from the tax bill.