Multiplan is spreadsheet program developed by Microsoft and introduced in 1982 as a competitor to VisiCalc.

Multiplan was released first for computers running CP/M; it was developed using a Microsoft proprietary p-code C compiler as part of a portability strategy that facilitated ports to systems such as MS-DOS, Xenix, Commodore 64 and 128, TI-99/4A (on four 6K GROMs and a single 8K ROM), Radio Shack TRS-80 Model II, TRS-80 Model 4, TRS-80 Model 100 (on ROM), Apple II, AT&T UNIX PC, and Burroughs B20 series. The CP/M version also ran on the TRS-80 Model II and 4, Commodore 128, and Apple II with a CP/M card. In France, Multiplan was also released for the Thomson computers in 1986 and same year on Japan for MSX compatible computers with name MSX-Plan.

Despite the release of Microsoft Chart, a graphics companion program, Multiplan continued to be outsold by Lotus 1-2-3. Multiplan was replaced by Microsoft Excel, which followed some years later on both the Apple Macintosh (1985) and Microsoft Windows (1987).

Although over a million copies were sold, Multiplan was not able to mount an effective challenge to Lotus 1-2-3. According to Bill Gates, this was due to the excessive number of ports (there were approximately 100 different versions of Multiplan). He also believed that it was a mistake to release 8-bit versions instead of focusing on the newer 16-bit machines and as a result, "We decided to let [Lotus] have the character-based DOS market while we would instead focus on the next generation–graphical software on the Macintosh and Windows." Around 1983, during the development of the first release of Windows, Microsoft had plans to make a Windows version. However the plans changed a year later.

A version was available for the Apple Lisa 2 running Microsoft/SCO Xenix 3. It fit on one 400K microfloppy diskette.