We identified risk factors for postoperative anxiety and quantified their effect on 712 adults between 18 and 60 years of age (ASA I–III physical status) undergoing elective surgery under general anaesthesia, neural blockade or both. The measuring instruments were a structured questionnaire, a pain visual analogue scale, the McGill Pain Questionnaire, the State‐Trait Anxiety Inventory, the Montgomery–Äsberg Depression Rating Scale, a Self‐Reporting Questionnaire‐20, and a Self‐Perception of Future Questionnaire. Multivariate conditional regression modelling taking into account the hierarchical relationship between risk factors revealed that postoperative anxiety was associated with ASA status III (OR = 1.48), history of smoking (1.62), moderate to intense postoperative pain (OR = 2.62) and high pain rating index (OR = 2.35), minor psychiatric disorders (OR = 1.87), pre‐operative state‐anxiety (OR = 2.65), and negative future perception (OR = 2.20). Neural block anaesthesia (OR = 0.72), systemic multimodal analgesia (OR = 0.62) and neuroaxial opioids with or without local anaesthesia (OR = 0.63) were found to be protective factors against postoperative anxiety.