Gallbladder diseases are among the most common gastrointestinal conditions encountered in outpatient settings, with some evidence suggesting a higher prevalence among individuals with diabetes mellitus. This cross-sectional study aimed to identify risk factors associated with gallbladder diseases, particularly cholelithiasis and cholecystitis, and to evaluate the relationship between type 2 diabetes mellitus and gallbladder disease in symptomatic patients. The study was conducted over six months across multiple tertiary care hospitals in Rawalpindi and Islamabad and included 254 symptomatic patients presenting to surgical departments. Data were collected using a structured questionnaire, and statistical analysis was performed using SPSS version 27. The majority of participants were female (72.8%) and over 45 years of age (53.1%), with 53.9% having a normal body mass index. Type 2 diabetes mellitus was present in 24.8% of patients, and gallbladder disease was detected on ultrasound in 82.3% of cases. A significant association was observed between gallbladder disease and the use of estrogen–progestin medications (p = 0.010). No significant associations were found with diabetes mellitus, age, gender, body mass index, smoking status, physical activity, hypertension, lipid-lowering medication use, family history of diabetes, or parity. The findings indicate that type 2 diabetes mellitus is not significantly associated with gallbladder disease among symptomatic patients in this regional population, while hormonal medication use may represent an important risk factor.