Objective: The purpose of the study was to assess the relation between the age of onset of cognitive impairment and multilingualism in patients assessed in a specialist clinic in north India Methods: Case records of 76 consecutive patients diagnosed in a speciality clinic were reviewed. The age of onset of cognitive impairment was compared between monolinguals and bilinguals. Results: In our study, in Bilinguals age of onset of cognitive impairment was delayed by around eight years. Along with bilingualism, years of education was also seen to influence the age of onset of cognitive impairment. Conclusion: This is a first study done in north India comparing bilingualism and age of onset of cognition of patients in a speciality clinic. The study shows the beneficial effect of bilingualism on age of onset of cognitive impairment by delaying the onset by around 8 year