At the same time, casualties among Afghan troops rose significantly as they took the lead in the 12-year war against the Taliban.
The figures underline the dangers this nation still faces as the NATO-led mission nears its end chapter in Afghanistan in 2014.
According to the AP tally, NATO casualties fell to 151 in 2013, down from 394 a year earlier.
However, foreign troops are still targeted by insurgents. Just last week, a suicide bomber struck a convoy in the capital, Kabul, killing three NATO troops, including one American.