Background: Smoking and obesity are well-known risk factors for surgical site infection, but it is unknown whether these factors influence outcomes after repair of small umbilical and epigastric hernias with defects ≤2 cm. The aim of this study was to evaluate whether smoking and obesity are associated with readmission, reoperation for complications, and recurrence rates after elective repair of small umbilical and epigastric hernias. Methods: Data on hernia type, size, repair method, smoking status, and body mass index after elective repair were available from the Danish Hernia Database from January 2017 through December 2018. Data on 90-day readmission and reoperation were available from the Danish National Patients Registry. Results: A total of 1,965 patients were included for final analysis, of whom 85.1% (1,672 of 1,965) were repaired by open approach and 70.8% (1,391 of 1,965) with mesh reinforcement. A 100% follow-up was secured, and median follow-up time was 307 (138–432) days. Readmission was significantly higher in smokers (9.6% [34 of 353]) compared with nonsmokers (6.4% [103 of 1,612]), P = .030. The reoperation rate for complications was also significantly higher for smokers (4.0% [14 of 353])) compared with nonsmokers (2.0% [32 of 1,612]) (P = .026). Patients with a body mass index ≥35 kg/m² were more frequently readmitted (11.7%; 12 of 102) compared with 6.7% (125 of 1,965) of patients with body mass index ≤34.9 kg/m² (P = .046). In multivariate analyses adjusted for age, sex, presence of chronic obstructive pulmonary disease, diabetes, and cardiovascular disease, smoking (odds ratio = 1.52 [1.02–2.30]) and body mass index >40 kg/m² (odds ratio = 6.07 [2.03–18.10]) were independent risk factors for readmission. Conclusion: Smoking and obesity have a significantly negative impact on outcomes even after elective repair of small umbilical and epigastric hernias.