Announced simultaneously with the Model 757, the Boeing Model 767 introduced a completely new fuselage structure which is 1.24m wider, providing seven- or eight- abreast seating with two aisles. Planned layouts cater for 211 mixed-class passengers, comprising 18 first-class in six-abreast accommodation, with the remaining 193 tourist:class seated seven-abreast; or 230 tourist-class in all seven-abreast seating; or a high-density eight-abreast configuration for a maximum of 289 passengers; but there are also other options. The go-ahead for the Model 767 programme was announced on 14 July 1978, following receipt of an order for 30 of these aircraft from United Airlines: in March 1990 orders and options totalled 483.

Computer Aided Design (CAD) was used to speed the preparation of drawings for much of the principal structure, their high accuracy being of great benefit when, as in this case, a large amount of the construction is being carried out by other companies. These include Aeritalia, Canadair, Grumman and Vought, plus a Japanese consortium, known as the Civil Transport Development Corporation, that comprises Fuji, Kawasaki and Mitsubishi. Together, 28 companies are manufacturing assemblies and components which, in terms of value, represent some 45% of the total cost.

Wing design differs somewhat from that of the Model 757, and features increased sweepback, and greater span and wing chord, to provide approximately 53% increase in wing area. The tail unit and landing gear are similar in configuration, and the Model 767 shares with the Model 757 twin turbofan engines pod-mounted beneath the wings. These, however, are of greater thrust in the Model 767, with alternative Pratt & Whitney JT9D-7R4D and General Electric CF6-80A powerplants, each in the 21,772kg thrust class, being specified by early airlines. Later GE and PW engines are now on offer, along with the Rolls-Royce RB211.

Boeing planned initially to offer two versions: a Model 767-100 with a shorterfuselage and accommodation for approximately 180 passengers, and the basic Model 767-200 described above. It was then decided not to build the shorter-fuselaged Model 767-100, and instead the Model 767-200 is available at alternative gross weights. Thus the version which was ordered initially by United Airlines for US domestic service has a maximum take-off weight of 127,913kg. That, with a gross weight of 140,614kg, can carry 211 passengers over a range of up to 6013km, making it suitable for non-stop transcontinental services, and also for many international routes.

With an optional flight crew of two or three, provided with the same avionics equipment as described for the Model 757, this new airliner demonstrates seat-mile costs some 32% below that of other wide-body tri-jets. The new fuselage also offers significant air freight capacity, with a cargo hold able to accept up to 22.LD-2 containers, or LD-3/-4/-8 containers to similar volume. With the inclusion of an optional forward cargo door measuring 1.75m by 3.4m, Type 2 pallets can be loaded. The first Model 767 was rolled out at Everett, Washington, on 4 August 1981, and made a 2 hour 4 minute maiden flight there on 26 September, which was a few days ahead of the target date set when the programme was launched in 1978.

In February 1983 Boeing announced the 767-300, featuring a 6.42m fuselage stretch to cater for additional capacity. Both -200 and -300 are offered in ER (Extended Range) variants, with increased fuel capacity and take-off weight for long-range operations.