USB-C on cameras explained: speeds, cables, charging and why some won't tether to a phone

Short answer: USB-C is a connector, not a speed. A camera's USB-C port can run anywhere from 480Mbps (USB 2) to 10Gbps (USB 3.2 Gen 2), and the slowest of the camera, the cable and the phone sets the pace. Standard iPhones run USB-C at USB 2 speed; Pro models from the iPhone 15 Pro on reach 10Gbps with a 10Gbps cable. For tethering to a phone, any short data cable works; speed matters most for big RAW files. When a camera won't tether, the usual culprits are its USB mode, a charge-only cable, or the camera trying to draw power from the phone.

The speeds, decoded

USB names have changed several times. The USB-IF's current consumer names describe speed directly, while the older names live on in spec sheets.

Maximum rates are theoretical. Real transfers are slower because of protocol overhead and because the camera has to read each file from its card. Even so, the gap between USB 2 and USB 3 is real for large RAW files tethered to a computer.

What the speed means per photo

A 50 MB RAW file is 400 megabits. At USB 2's 480 Mbit/s the wire alone needs at least 0.8 s; at 10Gbps it's 0.04 s. In practice the camera and phone add time on top. In CloudTether's app logs, a Canon EOS R5 Mark II JPEG reached the phone in a median 0.06 s over USB against 0.20 s over Wi-Fi, and EOS R1 users' median 33 MB CR3 RAW files arrived in 1.46 s over USB. For JPEGs, any USB link is effectively instant; the upload from the phone to the cloud is usually the slower leg. See our USB vs Wi-Fi tethering speed test.

Phones: often the real limit

Apple's iPhone 18 Pro lists USB 3 at up to 10Gb/s, with a footnote that a USB 3 cable rated at 10Gb/s is required. The standard iPhone 15, 16, 16e, 17 and 17e and the iPhone Air run at USB 2 speed, as do Lightning iPhones through Apple's camera adapter. The 1 m cable in an iPhone box is a charge cable at USB 2 speed. Android phones vary widely: check whether the spec sheet says USB 2.0 or USB 3.x, and whether the phone supports USB host (OTG), which almost every current model does. Our iPhone tethering and Android tethering pages cover each platform.

Cables: data, rating and length

• It must carry data. Many USB-C cables are charge-only. A camera that charges but never appears on the phone is the giveaway.
• It must be rated for the speed you want. A 10Gbps link needs a cable marked 10Gbps (or USB 3.2 Gen 2). A USB 2 cable works, just at USB 2 speed.
• Shorter is better. Commonly cited limits for passive USB-C cables are about 4 m for USB 2, 2 m for 5Gbps and 1 m for 10Gbps. For a phone on the camera, 30 cm to 1 m is plenty.
• Plug in directly. Unpowered hubs and stacked adapters are a common cause of dropouts.

If your camera has an older port, use a single cable with the right plug at each end rather than a chain of adapters. Our tethering cable guide and tether cable picker find the right one for your body.

Power delivery and charging

USB Power Delivery lets two devices agree how much power flows and in which direction. Many cameras can charge, or run, from a USB PD source; Sony's α7R VI dedicates its second USB-C port to Power Delivery, and its DC-C2 coupler needs a PD source of 100 W or more. The catch with phones is direction. An iPhone with USB-C can supply only up to 4.5 W to an accessory, so a camera that tries to charge itself from the phone drains the phone and may still not get enough power. Sony's FTP guide recommends a phone and cable that support USB PD when the camera tethers through a phone.

Practical fixes: turn off USB power supply or charging from the camera's menu when tethering to a phone where the camera allows it (on recent Fujifilm bodies, USB POWER SUPPLY/COMM SETTING has a POWER SUPPLY OFF/COMM ON option), and charge the phone from a power bank rather than the other way round.

Why some cameras won't tether to a phone

1. The wrong USB mode. Tethering needs the camera's PTP or remote mode, not mass storage, webcam or streaming. A Sony ZV-E10 defaults to USB streaming and must be switched to PC Remote; Fujifilm needs USB TETHER SHOOTING AUTO; on Canon, make sure the camera isn't in a webcam or streaming mode and turn its Wi-Fi off before plugging in.
2. A charge-only cable. Swap it for a known data cable.
3. The camera only acts as a card reader. Action cameras and some compacts offer mass storage only, which a tethering app can't use to see each new shot.
4. Power. The camera pulls power from the phone and the link drops. Disable USB charging on the camera or power the phone separately.
5. The card. On iPhone we've seen a Nikon with a CFexpress card refuse a USB connection until the card was formatted in the camera.
6. Adapters and hubs. A Lightning iPhone needs Apple's Lightning to USB 3 Camera Adapter; avoid unpowered hubs.

If it still won't connect, work through camera not detected over USB and iPhone camera adapter not working.

What to buy

For a USB-C camera and a USB-C phone: one short USB-C to USB-C data cable rated 10Gbps (it works at any lower speed too), a spare, and a USB-PD power bank for the phone. That covers tethering to a phone with CloudTether, offloading to a laptop and charging on the go.