The United States' balance of payments on a current-account basis moved into surplus last year for the first time since 1976, but that surplus was unexpectedly small at $118 million, Commerce Department figures revealed yesterday. In 1979 the United States ran a deficit of $705 million.

The surplus shrank from $4.5 billion in the third quarter to $700 million in the fourth.

The current account includes trade in goods such as cars and food and in services such as shipping or travel, and interest and dividends on overseas investments.

Merchandise trade alone showed a deficit of $27.4 billion last year. During the final quarter of 1980 the current account surplus shrank mainly because the merchandise trade gap worsened as U.S. imports rose much more rapidly than exports.

The overall current surplus for the fourth quarter reflected a deficit on merchandise trade of $6.1 billion, with an offsetting surplus on other current account items such as shipping, travel, interest and dividend receipts and payments on overseas and foreign investment.

The surplus means broadly that the United States is selling or exporting more goods and services to the rest of the world than it is buying from overseas. The improvement in the U.S. payments position that came in the middle of last year was largely due to the onset of recession. As economic activity picked up sharply towards the end of 1980, imports began to rise more rapidly than exports.

The latest official prediction for the balance of payments this year is that there will be a further improvement of "a few billion" dollars in the merchandise trade balance. But this forecast was made before the trade figures for January were released. These showed a further deterioration in the trade balance.

Meanwhile, the International Monetary Fund reported yesterday that the world's major industrialized countries had their biggest trade deficit in history in 1980. The rise in oil prices throughout 1979 pushed many of those countries into deficit, and cut the surpluses of others such as West Germany.

Although the U.S. deficit was the largest, the IMF noted the improvement during the year which helped to strengthen the dollar while other currencies slipped, in particular the mark.

The IMF said the industrialized countries' trade was $129.6 billion in the red, with a 17.1 percent rise in exports outweighed by a 19.7 percent increase in imports.

The United States had a surplus of $9.13 billion in services trade in the final quarter of last year, slightly up from the third-quarter total of $8.88 billion, the Commerce Department report showed.

Earnings on U.S. direct investments overseas dropped noticeably last year.