President Reagan and his wife, Nancy, made $418,826 in 1981 and paid nearly 40 percent of it in federal income taxes, according to returns made public at the White House without comment yesterday.

The Reagans' joint return shows that they paid income taxes of $165,305 and claimed charitable deductions of $11,895. Nearly half of this ($5,930) was in clothes donated by Mrs. Reagan to two museums two weeks before her husband was inaugurated president.

The Reagans made $5,965 in cash contributions to charities, 1.4 percent of his total income. They gave the same percentage to charity in 1980.

At a news conference on Jan. 19 the president said he realized "that some have noticed that there seemed to be a small percentage of deductions for worthwhile causes, and that is true. And I'm afraid it will be true this year, because I haven't changed my habits, but I also happen to be someone who believes in tithing--the giving of a tenth."

Reagan went on to say that he had made gifts over the years that were not tax deductible. The president and White House officials have declined to identify the recipients of these contributions.

"My conscience is clear as to what I have been giving," Reagan said.

A separate sheet attached to the tax return said that the non-cash contributions were appraised by the Robert S. Scott Co. to the Fashion Institute of Design and Merchandising Museum and the Los Angeles County Museum of Art. White House deputy press secretary Larry Speakes, on information supplied by Reagan accountant Roy D. Miller, identified the items as personal clothing owned by Mrs. Reagan.

White House officials acknowledged that Mrs. Reagan received thousands of dollars worth of designer clothing on loan last year. Some tax lawyers have said this should be treated as taxable income, while others have disputed this interpretation.

None of this clothing was declared as income on the joint return.

Reagan earns $200,000 a year as president. His presidential salary in 1981, however, was $189,167, because he did not take office until Jan. 20.

The president's other income included $42,635 in royalties and payments for past writings, radio or acting performances, $66,558 from investments made by his blind trust and $51,482 for a past property sale.

Reagan also receives a pension of $22,197 from the state of California, where he was governor for eight years.