Background: For cosmetics, it is mandatory to label 26 fragrance substances, including all constituents of fragrance mix I (FM I) and fragrance mix II (FM II). Earlier reports have not included oxidized R-limonene [hydroperoxides of R-limonene (Lim-OOH)] and oxidized linalool [hydroperoxides of linalool (Lin-OOH)], and breakdown testing of FM I and FM II has mainly been performed in selected, mix-positive patients. Objectives: To report the prevalence of sensitization to the 26 fragrances, and to assess concomitant reactivity to FM I and/or FM II. Methods: A cross-sectional study on consecutive dermatitis patients patch tested with the 26 fragrances and the European baseline series from 2010 to 2015 at a single university clinic was performed. Results: Of 6004 patients, 940 (15.7%, 95%CI: 14.7–16.6%) were fragrance-sensitized. Regarding the single fragrances, most patients were sensitized to Lin-OOH (3.9%), Evernia furfuracea (3.0%), Lim-OOH (2.5%), and hydroxyisohexyl 3-cyclohexene carboxaldehyde (2.1%). Significantly fewer patients were ‘FM I-positive and constituent-positive’ than ‘FM II-positive and constituent-positive’ (32.7% versus 57.0%, p < 0.0001). Additionally, significantly more patients were ‘FM II-negative but constituent-positive’ than ‘FM I-negative but constituent-positive’ (12.4% versus 3.2%, p = 0.0008). Conclusions: Non-mix fragrances are the most important single fragrance allergens among consecutive patients. The test concentration of the single FM I constituents should be increased when possible.