Purpose: To determine whether smokers report having less adequate oral hygiene habits than nonsmokers. Materials and Methods: Using a 24-item questionnaire addressing both smoking and oral hygiene habits, patients from three periodontal practices in Spain were evaluated. In order to assess the periodontal status of all patients, immediately following the survey, the patients were examined clinically and categorised according to the American Dental Association (ADA) classification for periodontal diseases. Results: 762 patients with ADA type I gingivitis (4.1%), type II early periodontitis (31.2%), type III moderate periodontitis (39.2%) and type IV advanced periodontitis (25.5%) were surveyed. A total of 289 smokers (38.0%) and 402 (52.8%) nonsmokers participated in the study: 77 (10.1%) participants were identified as heavy smokers (>20 cigarettes/day), along with 122 (16.0%) moderate smokers (10-20 cigarettes/day) and 90 (11.8%) light smokers (20 cigarettes/day). A greater proportion of nonsmokers brushed their teeth two (37.8%) or more (22.9%) times a day compared with moderate smokers (twice: 32.0%, more: 15.6%) and heavy smokers (twice: 32.5%, more: 15.6%), respectively (p 0.05). Heavy smokers used dental floss statistically significantly less frequently (10.4%) than nonsmokers (21.6%) (p 0.05). No statistically significant differences were found between smokers and nonsmokers regarding the use of mouthwashes (p > 0.05). Conclusions: This study revealed comparable oral hygiene habits in nonsmokers and light smokers. However, heavy smokers were found to have worse oral hygiene habits than nonsmokers. Schlagwörter: dental floss, mouthwash, oral hygiene habits, smoking, toothbrush