As of 2026, United Airlines has nearly completed its "United Next" fleet transformation, but the answer is still "not quite all, but most." Under the United Next initiative, all new aircraft (like the Boeing 737 MAX and Airbus A321neo) and retrofitted older planes feature power outlets at every single seat, including the back of the plane. These seats also typically include USB-A and USB-C ports. However, if you find yourself on a "legacy" aircraft that hasn't yet gone through the shop—specifically some older Boeing 737-700s or ERJ-145 regional jets—you may find that power is only available in First Class or Economy Plus, or not at all. United's goal was to have 100% mainline coverage by late 2025, but regional partners often lag behind. To be safe, travelers should check the "Amenities" tab on the United app 24 hours before flight, as it will specify if "Power" and "USB" are available for your specific tail number.