In frail older adults, antibiotics are often inappropriately prescribed for suspected urinary tract infections (UTIs). We describe three cases in the general practice, nursing home, and emergency department setting to illustrate how to improve diagnosing UTIs in frail older patients. Nonspecific symptoms, e.g., behavioral change or smelly urine, often trigger a UTI suspicion followed by immediate urine testing and antibiotic treatment. However, nonspecific symptoms should trigger a broad differential diagnosis and thorough evaluation. The value of urine tests is limited due to the high prevalence of asymptomatic bacteriuria in this patient group; a UTI is thus a clinical diagnosis not solely based on a positive urine test. Antibiotic treatment is recommended only in case of symptoms referable to the urinary tract or systemic symptoms in patients without a urinary catheter. In patients with a urinary catheter, antibiotic treatment is recommended in case of systemic symptoms without any other focus.