The surplus was $1.18 billion in February compared to a revised $154.7 million a month earlier, the Bank of Korea said.

The account -- the broadest measure of cross-border trade -- stayed in surplus for the 12th straight month in February thanks to strong exports.

The latest surplus is expected to strengthen the won, which has risen 1.83 percent to the dollar so far this year.

"Exports remained brisk and a shortfall in the service account narrowed last month as the winter vacation season wrapped up," a central bank official told Yonhap news agency.

He cautioned that a sharp rise in oil prices following political upheaval in the Middle East and North Africa was not fully reflected in the cost of last month's crude imports.

The goods balance recorded a surplus of $1.58 billion in February, up from a revised $1.56 billion in January.

A shortfall in the service account, which includes spending on overseas trips, narrowed to $569.1 million in February compared with a $1.64 billion deficit the previous month.