In December, the biggest European economy had recorded a surplus of 10.7 billion euros, the Destatis office said.
Economists polled by Thomson Financial News had forecast a €15 billion surplus in January.
Despite the euro climbing toward record highs, German exports increased by 3.8 percent on a monthly basis, though imports grew by 4.2 percent, the seasonally corrected data showed.
Germany’s current account – the widest measure of its trade and financial transactions with other countries – ended January with a surplus of €15 billion, down from €16.8 billion one month earlier.