Logo of the L-mount alliance | |
| Type | Bayonet, digital interface |
|---|---|
| Inner diameter | 51.6 mm |
| Tabs | 4 |
| Flange | 20 mm |
| Connectors | 10 electrical pins |
The Leica L-Mount is a bayonet mount developed by Leica Camera AG for interchangeable-lens autofocus digital cameras.
The L-Mount has an inner diameter of 51.6 mm and a flange depth of 20.0 mm. The L-mount exists in two versions, an APS-C version (TL) and a full-frame version (SL). The two versions are mechanically and electronically compatible. TL lenses mounted on full-frame cameras will cause the camera to use a crop mode from the center of the sensor, corresponding to the APS-C coverage of the lens. SL lenses mounted on TL cameras function normally, providing a 1.5x crop field of view, as is typical with APS-C cameras.
In 2018 Leica formed the L-Mount Alliance, licensing Sigma, Panasonic in the same year, to use an upgraded version of the mount for their own products, opening the way for a more extensive system of fully compatible cameras and lenses.
Ernst Leitz Wetzlar GmbH, the cine lens business of Leica, joined the L-Mount Alliance in 2021, DJI followed in 2022, Samyang, Astrodesign, Blackmagic Design in 2023, Sirui, Viltrox in 2025 and Freefly Systems in 2026.

It was introduced in April 2014 with the Leica T (Typ 701) camera. At the time of introduction, it was called the "T-mount", but this was changed to "L-mount" with the release of the Leica SL, a full-frame sensor camera using the same mount. The Leica T was renamed to the Leica TL at this time, to permit marketing clarity for the L-mount lens line: TL lenses would cover APS-C sensors, while SL lenses would cover full-frame sensors.
The mount is used by the Leica TL (discontinued), TL2, Leica CL (2017) and Leica SL systems. The L-Mount is a registered trademark of Leica Camera AG.
On 25 September 2018, Leica Camera AG, Panasonic and the Sigma Corporation launched together The L-Mount Alliance. This allowed Panasonic and Sigma to make use of the L-Mount standard initially developed by Leica, to offer cameras and lenses utilizing this lens mount with improved firmware and full compatibility among products of the alliance. On the same day, both Sigma and Panasonic announced new products compatible with the L-mount.
Sigma announced a full-frame L-mount camera using the company's unique Foveon X3 sensor technology. Sigma will initially release the same L-mount variants of existing lenses as they are producing for the.
Sigma announced that it would launch a full-frame camera in 2019, using the L-Mount and the company's Foveon X3 sensor. The also announced a range of L-mount variants of their existing Sony E-mount lenses, and lens adapters for existing Sigma SA-mount and Canon EF mount lenses. According to Sigma CEO, Kazuto Yamaki, the improved "L-mount system is not exactly the same as the existing one. We updated it a little bit to work better with such lenses through lens adapters."
Panasonic announced its S1R and S1 full-frame L-Mount cameras and three L-Mount lenses, with seven more lenses to be launched by 2020.
Six cameras and 39 native lenses have been announced for the L-Mount by 2020.[needs update]
Next company to join the alliance was German cinema lens maker Ernst Leitz Wetzlar GmbH in 2021, later renamed Leitz Cine. It since has been followed by a number of other camera and lens manufacturers.
| № | Member | Since | Mainstream cameras |
Lenses | Specialized/cinema cameras and gimbals |
Drones |
|---|---|---|---|---|---|---|
| 1 | Leica | 25 September 2018 | ||||
| 2 | Panasonic | 25 September 2018 | ||||
| 3 | Sigma | 25 September 2018 | ||||
| 4 | Leitz Cine | 14 October 2021 | ||||
| 5 | DJI | 15 June 2022 | ||||
| 6 | Astrodesign | 14 July 2023 | ||||
| 7 | Samyang | 14 July 2023 | ||||
| 8 | Blackmagic Design | 15 September 2023 | ||||
| 9 | Sirui | 20 March 2025 | ||||
| 10 | Viltrox | 1 September 2025 | ||||
| 11 | Freefly Systems | 17 April 2026 |
Despite not being alliance members, some other brands, such as 7Artisans, TTartisan, AstrHori and Meike, have also introduced their autofocusing lenses for L-mount.
Leica T/TL cameras use APS-C sensors. The TL mount version is not dust- or splashproof. Discontinued models:
Leica SL cameras use full frame sensors. The SL version is dust- and splashproof.

The Unspecified Foveon-based full-frame camera Sigma initially announced at the original event has been withdrawn.
Leica has an existing range of fifteen L-Mount lenses.
Panasonic committed to releasing a total of ten lenses for the L-mount by the end of 2020, beginning with the 50mm F/1.4 prime and the two zooms listed below; stating that they would provide details at Photokina 2019.
Sigma plans to release a wide range of lenses. 14 primes from Sigma's 'Global Vision' range, primarily designed for reflex cameras with short flange depths and currently available for the mirrorless Sony E-mount, will also be released in L-Mount from 2019. These will be followed by a range designed specifically for mirrorless parameters.

Manual third-party lenses are being produced in L-mount by Irix, 7Artisans (Photoelectric series), Meyer-Optik (Görlitz series), and Kipon HandeVision (IBELUX and IBERIT series').[citation needed]