When established, the park covered an area of 12.000 km2, but with recent additions of Lakagígar, Langisjór and Krepputunga it now covers 13.920 km2 or approximately 14% of Iceland, making it Europe's second largest national park in terms of area after Yugyd Va in Russia.
Narodni park Vatnajökull je eden od treh narodnih parkov na Islandiji.