If you want the short answer first, the Canon EOS R6 Mark II uses SD, SDHC, and SDXC cards, and it has two card slots. Both slots are UHS-II compatible, and both can also use UHS-I cards. It does not use CFexpress cards.
Quick answer
- Card type: SD / SDHC / SDXC
- Slots: 2
- Slot type: both are UHS-II SD slots
- UHS-I cards: yes, officially supported
- CFexpress: no
Canon R6 Mark II Guide: See all Canon EOS R6 Mark II setup and gear answers in one place.
Table of contents
What card type does the Canon R6 Mark II use?
The EOS R6 Mark II uses SD cards, not CFexpress. Canon lists compatibility with SD, SDHC, and SDXC memory cards, and confirms support for both UHS-II and UHS-I cards.
That is the most important thing to get right before you buy cards. Some newer cameras in the EOS R line use a mixed slot setup, but the R6 Mark II does not. If you are shopping for this body, you are buying SD cards.
Are both card slots the same?
Yes. The R6 Mark II has dual card slots, and both slots are UHS-II compatible.
That matters for two reasons. First, you can run matched cards for backup, relay recording, or separate stills/video storage without having one slower slot dragging the setup down. Second, it makes the camera easier to buy for because you do not need one SD card and one CFexpress card.
What card speed do you actually need?
A slower UHS-I card can still work for lighter stills use and lower-demand video modes, but the R6 Mark II makes better use of faster media when you start leaning on bursts, 10-bit video, or higher-bitrate recording.
- Casual stills and light video: a good UHS-I U3 / V30 card may be enough
- Heavy bursts and faster buffer clearing: UHS-II is the safer choice
- Serious video: buy for the required speed class, not just the card label
Canon’s own burst-depth table shows that faster cards can make a visible difference in how long the camera keeps shooting before slowing down. That does not raise the top frame rate, but it can improve how usable the camera feels when you shoot long bursts.
What matters for 4K and 10-bit video?
Card speed matters more once you step into the R6 Mark II’s heavier movie modes. Canon says some modes need UHS Speed Class 3 or higher, while some 10-bit Canon Log 3 and HDR PQ modes need Video Speed Class V60 or higher.
That is why a vague “just buy any SD card” recommendation is not enough for this camera. If you plan to shoot 10-bit 4K, high-frame-rate Full HD, or longer clips, you want cards with real write-speed headroom.
Canon also notes there is no 4 GB file limit with an exFAT-formatted SDXC card, which is useful if you shoot longer clips and want fewer file-splitting annoyances.
What should most buyers buy?
For most people, the safe recommendation is simple: buy SDXC UHS-II cards, ideally V60 or faster, especially if you care about 10-bit video, high-frame-rate clips, or faster burst recovery.
- Best general choice: SDXC UHS-II V60
- For dual-slot backup: use two cards with similar speed and capacity
- For light stills only: a good UHS-I card can still be fine
The plain-English version is this: the Canon R6 Mark II takes SD cards, not CFexpress, and both slots are UHS-II. If you want one safe buying rule, choose good UHS-II SDXC cards and stop overthinking it.
More Canon R6 Mark II help: Back to the Canon R6 Mark II Guide
Brad is a seasoned photographer whose journey began in 2006 with a 3.1-megapixel digital camera. Over the years, he has specialized in various photography genres—from weddings and portraiture to product and studio photography. Based on the Sunshine Coast of QLD, Brad combines his love for education and photography, sharing his expertise on DSLRAD.com, a platform committed to capturing life’s treasured moments and empowering photography enthusiasts.