Delta's Boeing 767-300 seats 261 passengers, but the plane's seating capacity depends on the airline. The American Airlines version seats 209 passengers, and United Airlines offers two seating plans with room for either 183 or 214 people.
The Boeing 767-300 is popular for international travel, and each airplane's floor plan is separated into sections that offer different accommodations. United Airlines offers larger sleeping spaces in its United Global First and United Business First sections, where passengers can fully recline on longer flights. This accounts for United Airlines' lower seat count as compared to airlines that offer seats that only partially recline.