Plant-based diets may increase the risk of vitamin B12deficiency due to limited intake of animal-source foods, while dietary folate increases when adhering to plant-based diets. In this cross-sectional study, we evaluated the B12and folate status of Norwegian vegans and vegetarians using dietary B12intake, B12and folic acid supplement use, and biomarkers (serum B12(B12), plasma total homocysteine (tHcy), plasma methylmalonic acid (MMA) and serum folate). Vegans (n115) and vegetarians (n90) completed a 24-h dietary recall and a FFQ and provided a non-fasting blood sample. cB12, a combined indicator for evaluation of B12status, was calculated. B12status was adequate in both vegans and vegetarians according to the cB12indicator; however 4 % had elevated B12. Serum B12, tHcy, MMA concentrations and the cB12indicator (overall median: 357 pmol/l, 9·0 µmol/l, 0·18 µmol/l, 1·30 (cB12)) did not differ between vegans and vegetarians, unlike for folate (vegans: 25·8 nmol/l, vegetarians: 21·6 nmol/l,P= 0·027). Serum B12concentration < 221 pmol/l was found in 14 % of all participants. Vegetarians revealed the highest proportion of participants below the recommended daily intake of 2 µg/d including supplements (40v. 18 %,P< 0·001). Predictors of higher serum B12concentrations were average daily supplement use and older age. Folate deficiency (< 10 nmol/l) was uncommon overall (< 2·5 %). The combined indicator cB12suggested that none of the participants was B12-depleted; however, low serum B12concentration was found in 14 % of the participants. Folate concentrations were adequate, indicating adequate folate intake in Norwegian vegans and vegetarians.