The lens mount decides which lenses fit your camera. It also quietly decides what you will spend over the next ten years. Here are the main mirrorless systems.
The main mounts
| Mount | Makers | Sensor sizes |
|---|---|---|
| Sony E | Sony | Full frame and APS-C |
| Canon RF | Canon | Full frame and APS-C (RF-S lenses) |
| Nikon Z | Nikon | Full frame and APS-C (DX lenses) |
| Fujifilm X | Fujifilm | APS-C |
| Fujifilm G | Fujifilm | Medium format |
| L-mount | Leica, Panasonic, Sigma | Full frame and APS-C |
| Micro Four Thirds | OM System, Panasonic and others | Micro Four Thirds |
What to check before committing
Native lens lineup. Look for the lenses you will actually buy: a fast prime, a standard zoom, a telephoto if you shoot wildlife or sport.
Third-party lenses. Some mounts have broad third-party support, which usually means lower prices and more choice. Others are more limited. Check the specific lens and mount before assuming it works with autofocus.
Used market. A deep used market makes it cheaper to build a kit over time.
Adapters. You can adapt many older and cross-brand lenses, but expect trade-offs in autofocus speed and features.
APS-C and full frame inside one mount
Several mounts cover both formats. This is a smart upgrade path: start on APS-C, keep your full-frame-compatible lenses and move to a full-frame body later without starting over.
How to decide
- List the three lenses you most want.
- Check which mounts offer them at a price you accept.
- Pick the body you like inside that mount.
Read how to choose your first mirrorless camera for the full process.
Frequently asked questions
Can I use lenses from one brand on another brand's camera?
Sometimes, with an adapter, but autofocus and features can be limited. The simplest path is to buy lenses native to the mount you chose.
Can I use full-frame lenses on an APS-C body?
Yes, on the same mount. You get the cropped field of view. APS-C lenses on a full-frame body usually force a crop mode.
Which mount is the best?
None wins outright. Choose by the lenses you want, the body you like and your budget. Check native and third-party options before you buy.