Heterogeneity in clinical presentation and daytime somnolence in restless legs syndrome (RLS) have been poorly explored in the UK. Analysis of database of 152 cases of primary RLS compiled from clinical consultation using a structured questionnaire administration and clinical examination, spanning six years of referral. Standard evaluations included use of the Epworth Sleepiness Scale (ESS). Secondary RLS was excluded and polysomnography performed in some when clinically indicated. The mean duration of RLS before appropriate treatment initiation was 12.7 years (age range of patients 26-90 years). 79% of patients had insomnia while 30% had excessive daytime sleepiness (EDS). Severe pain, restless arms and paroxysmal RLS causing lifestyle alterations also occurred. This study suggests that there is considerable delay before appropriate therapy in RLS. A large number have EDS and insomnia among others, is the commonest presenting feature. Phenotypic heterogeneity may cause diagnostic difficulty.