India ranks second in the world after China with 74.2 million living with diabetes currently and is projected to see 124.9 million living with diabetes by 2045. Diabetics need extensive self-management support, medications, regular screening for management of complications and comorbidities, which can increase out-of-pocket (OOP) expenditure for patients and their families. The aim of this article is to estimate the OOP expenditure for the management of diabetes mellitus and its complications among residents of slum areas of Agra city and to find out the association of OOP expenditure with sociodemographic and diabetic profile and compliance to treatment among the study participants. A cross-sectional study through face-to-face interviews using predesigned, pretested, and semistructured questionnaires were conducted from October 2020 to September 2022. A sample of 360 known diabetics was included. Statistical analysis was done using IBM SPSS version 24 and descriptive statistics were reported wherever applicable. Male, female ratio was 3:2, 66% of participants were between 35 and 60 years, 28% were illiterates, 54% were unemployed and 44% were from upper lower socioeconomic class. Nearly 96% were type 2 diabetics and 74% were on oral hypoglycemic agents. Monthly median direct and indirect OOP expenses were INR 1,500 and INR 505, respectively. OOP expenses were borne by 98% of the study participants.