McDonald's typically starts serving lunch at around 10:30 a.m. local time on weekdays. On weekends, the start time can vary slightly, usually between 10:30 a.m. and 11:00 a.m., depending on the location. This means that after breakfast hours end, usually at 10:30 or 11:00 a.m., the lunch menu becomes available. However, since local franchisees decide their exact hours, it's best to check with your specific McDonald's location for precise times.