United Airlines (UAL.O) said on Friday it was adding more than 480 daily flights to its U.S. schedule in June to meet summer travel demand that is expected to rise as more people receive COVID-19 vaccines. Airlines are seeing an uptick in bookings as accelerated vaccination efforts encourage leisure travel with friends and family after months of pandemic-linked restrictions. "As leisure travel continues to return this summer, we are adding more flights to our June schedule," said Ankit Gupta, vice president of domestic planning and scheduling at United. The company said it plans to fly 67% of its domestic schedule and 60% of its overall schedule compared to 2019 June. The additions will include new flights to Hawaii, Alaska and Montana.