Background The advanced hybrid closed loop (AHCL) algorithm combines automated basal rates and corrections yet requires meal announcement for optimal performance, which poses a challenge for some. We aimed to compare glucose control in adults with T1D using the MiniMedTM 780G AHCL system utilizing simplified meal announcement versus precise carbohydrate counting. Methods In a study involving 14 adults with T1D, we evaluated glycemic control during a 13 week "precise phase", followed by two 3-4 week simplified meal announcement phases: "universal" (preset of one personalized fixed carbohydrate amount) and "incremental" (entry of multiples of one, two, or three of these presets depending on meal size estimate). Results Mean age was 45.7±12.4 and ten participants were male (71%). Mean baseline HbA1c was 6.8%±1.2% and TIR 67.5%±16.7%. Comparing the universal to the precise study phase, TIR was similar (75.4±13% vs. 77.7±9%, p=0.12) and GMI was slightly higher (6.8±0.4 vs. 6.6±0, p=0.01). Furthermore, there was less level 1 and 2 hypoglycemia (1.6±1% vs. 2.8±2%, p=0.03 and 0.3±5% vs. 0.65±1%, p=0.08), but slightly more level 1 and 2 hyperglycemia (17.1±8% vs. 15.0±7%, p=0.05 and 5.5±5% vs. 3.6±3%, p=0.04). When comparing the incremental to the precise phase, GMI was identical (6.6%) and TIR superior (80.5±10% vs. 77.7±9%, p=0.02). Additionally, there was less level 1 hypoglycemia (1.9±1% vs. 2.8±2%, p=0.01) and a trend for less level 2 hypoglycemia (0.4±0.7% vs. 0.65±1%, p=0.08). Conclusions A simplified meal announcement strategy in adults using the MiniMedTM780G system, relying on three increments of a universal CHO amount, may offer a way to improve glycemic control and ease self-care. For patients with more limitations, using one universal CHO amount could be a safe alternative meeting most consensus glycemic targets.