The Southern African Large Telescope is the single largest optical telescope in the southern hemisphere and the largest in Africa. It has an approximately 10-metre diameter spherical primary mirror, comprised of 91 identical hexagonal segments. The telescope is tilted at a fixed angle of 37 degrees from the zenith, so that it moves only in azimuth, rotating into position on air bearings and remaining stationary during each observation. Precise pointing and tracking are handled by the moving optical corrector assembly and instrument payload at the top of the telescope tube.

This design is based on the Hobby-Ebberly Telescope (HET) at the McDonald Observatory in Texas, which is one of the international partners in the project. However, this design has been altered in many ways to accommodate requirements specific to SALT and to take advantage of the opportunity to optimise aspects of the design where difficulties have been identified with the HET performance.

This design allowed SALT to be built at less than a fifth of the cost of a conventional telescope this size. Approximately one third of the funding for SALT has come from the South African government and roughly 60% of the construction and development budget was spent within the country.