1 definition found wasilla - U.S. Gazetteer (1990) : Wasilla, AK (city, FIPS 83080) Location: 61.58021 N, 149.46160 W Population (1990): 4028 (1723 housing units) Area: 29.0 sq km (land), 1.7 sq km (water) Zip code(s): 99654, 99687