Best Memory Card for Canon EOS R6 Mark III
The 32.5MP EOS R6 Mark III writes 7K RAW at 2600 Mbps and a 12 fps RAW burst past 1000 frames to slot 1: CFexpress Type B at 400 MB/s. Slot 2 is UHS-II SD, and that movie has no SD option. SanDisk Extreme PRO CFexpress Type B matches the bus — VPG400, 900 MB/s floor. Check Extreme PRO CFexpress Type B on Amazon.
Our Top Picks at a Glance
Reviewed September 2026 · EOS R6 Mark III · CFexpress Type B + UHS-II SD · 7K RAW 2600 Mbps · 12 fps 1000+ RAW · 40 fps 150 RAW
Type B, VPG400, 900 MB/s floor. Matches 7K RAW Standard and the 1000+ RAW burst on slot 1.
Check Price at Amazon Read full review ↓Slot 2. UHS-II V90, 300 / 300 MB/s. Overflow, backup, and 4K Intra 30p on SD.
Check Price at Amazon Read full review ↓Slot 2 stills and 4K Long GOP. V60 / U3. Not the Intra 60p card, and never 7K RAW.
Check Price at Amazon Read full review ↓This page contains affiliate links. A purchase through those links may earn Cameraegg a commission at no extra cost to you.
| Card | Slot / class | Rated speed | R6 Mark III job | Buy |
|---|---|---|---|---|
| SanDisk Extreme PRO CFexpress Type B | Slot 1 · Type B · VPG400 | 3700 / 3500 MB/s peak · 900 MB/s min (128–400 GB) | 7K RAW Standard 400 MB/s · 12 fps 1000+ RAW | Check price |
| SanDisk Extreme PRO UHS-II V90 | Slot 2 · UHS-II V90 | 300 / 300 MB/s · 90 MB/s min | Backup / overflow · 4K Intra 30p on SD | Check price |
| Lexar 1800x GOLD | Slot 2 · UHS-II V60 | 280 / 210 MB/s (64–128 GB) | Stills + 4K Long GOP (U3). Not Intra 60p. | Check price |
| Lexar GOLD CFexpress Type B | Slot 1 · Type B · CFexpress 2.0 | 1750 / 1500 MB/s · 1000 MB/s sustained | Same 400 MB/s floor, older 2.0 bus | Check price |
| SanDisk Extreme PRO UHS-I | UHS-I V30 | UHS-I bus | Records on slot 2. Wrong bus for this body. | Check price |
How We Picked
Three sourced facts: two different slots, a 400 MB/s CFexpress floor for 7K RAW, and Canon’s own SD test card.
- Weigh the slots, then the movie that only one of them can take. Canon EOS R6 Mark III specifications and B&H 7084C010: slot 1 is CFexpress Type B (CFexpress 2.0, VPG400, up to 8 TB); slot 2 is SD/SDHC/SDXC UHS-II. Mechanical / electronic first-curtain RAW burst: over 1000 frames on CFexpress, 400 on a 128 GB UHS-II SD card. Electronic shutter RAW: 150 / 140. 7K Standard RAW at 29.97p is 2600 Mbps and needs CFexpress 2.0 Type B at 400 MB/s or more; the SD column is a dash.
- Match VPG400 to that 400 MB/s floor. SanDisk Extreme PRO CFexpress 4.0 Type B: VPG400 and VPG800 on 128–400 GB, up to 3700 / 3500 MB/s peak, 900 MB/s minimum sustained write on those capacities. The camera speaks CFexpress 2.0; the VPG400 mark is what Canon lists, not the peak.
- Fill slot 2 to the class Canon tested, then size the CFexpress card for RAW minutes. Burst tables use a 128 GB UHS-II SD card. 4K Fine Long GOP is U3 on SD; XF-AVC S Intra High Quality at 29.97p asks V90, and Intra at 59.94p often cannot record to SD at all. Standard RAW at 29.97p is about 13 minutes on 256 GB and 3 minutes on 64 GB — 256 GB is the travel size for slot 1.
Detailed Reviews
SanDisk Extreme PRO CFexpress Type B View on Amazon View on B&H
| SKU family | SDCFEB — SanDisk Extreme PRO CFexpress 4.0 Type B |
|---|---|
| Class | CFexpress Type B · VPG400 / VPG800 (128–400 GB) |
| Peak / floor | Up to 3700 / 3500 MB/s · 900 MB/s min sustained (128–400 GB) |
| Capacity | Prefer 256 GB. 128 / 400 GB / 1–4 TB exist. Cards over 2 TB cannot update firmware. |
| Body job | Canon: 7K Standard RAW 400 MB/s, SD not allowed · 12 fps RAW over 1000 frames |
Why it fits the R6 Mark III. Slot 1 is Type B. 7K Standard RAW at 29.97p is 2600 Mbps and Canon’s card column is 400 MB/s CFexpress, not SD. SanDisk’s 128–400 GB cards carry VPG400 and a 900 MB/s floor, which is the class Canon lists. Peak 3700 MB/s is a reader figure; in camera the bus is CFexpress 2.0.
Buy 256 GB when RAW video is on the list — Canon’s table is 13 minutes of Standard RAW 29.97p on 256 GB, 3 minutes on 64 GB. Skip this card only if slot 1 stays empty and the day never needs 7K RAW or Intra 60p; that is a slot-2 body, not this body’s default.
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SanDisk Extreme PRO SDXC UHS-II V90 View on Amazon View on B&H
| SKU family | SDSDXDM — SanDisk Extreme PRO UHS-II V90 |
|---|---|
| Class | UHS-II · U3 · V90 (90 MB/s sustained) |
| Peak | Up to 300 MB/s read and 300 MB/s write |
| Capacity | Prefer 128 GB — the size Canon used for SD burst figures. 64 / 256 / 512 GB exist. |
| Body job | Canon SD burst tests: 128 GB UHS-II · Intra High Quality 29.97p listed as V90 |
Why it is Value. Slot 2 is UHS-II. Canon measured SD bursts on a 128 GB UHS-II card: 400 RAW at 12 fps, 140 RAW at 40 fps. 4K Fine Long GOP is U3. XF-AVC S Intra High Quality at 29.97p is the row that asks V90 on SD. Extreme PRO V90 is that class, and 128 GB matches the test card.
Use it as overflow, as a simultaneous backup, or as the proxy card. Skip it when slot 2 only sees stills and Long GOP — that job is V60. It cannot take 7K RAW; that movie has no SD column.
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Lexar Professional 1800x SDXC UHS-II GOLD View on Amazon View on B&H
| SKU family | Professional 1800x GOLD — Lexar |
|---|---|
| Class | UHS-II · U3 · V60 |
| Peak (64–128 GB) | Up to 280 MB/s read · up to 210 MB/s write |
| Peak (256 GB–1 TB) | 280 / 205 MB/s |
Why it is Budget. V60 guarantees 60 MB/s and U3. Canon’s 4K Fine Long GOP row on SD is U3, so 1800x GOLD is the cheaper slot-2 card for stills and that movie. Intra High Quality at 59.94p has no SD option; Intra High Quality at 29.97p lists V90. Keep 7K RAW on the CFexpress card.
Skip this when slot 2 has to record Intra 30p or 60p, or when the 12 fps RAW buffer on SD (400 frames) is the point of the second door — step to V90. Pair it with a flash for this body on a stills day, not as a substitute for slot 1.
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If You Need Something Else
A cheaper Type B card still clears Canon’s 400 MB/s floor. A UHS-I card still records on slot 2. Neither is the default kit.
Lexar Professional CFexpress Type B GOLD View on Amazon View on B&H
| SKU family | CFexpress 2.0 Type B GOLD — Lexar |
|---|---|
| Peak / sustained | Up to 1750 MB/s read · 1500 MB/s write · 1000 MB/s sustained |
| Capacities | 128 / 256 GB |
This is CFexpress 2.0, the bus Canon lists. 1000 MB/s sustained still sits above the 400 MB/s RAW movie floor. Take it when Extreme PRO 4.0 is the expensive row and 256 GB is enough. It is not VPG400 on Lexar’s sheet — the SanDisk card is, which is why Extreme PRO stays Overall. A starter RF lens does not change the slot.
Check Price on Amazon US, UK, CA, DE → Check Price on B&H
SanDisk Extreme PRO UHS-I V30 View on Amazon View on B&H
| Bus | UHS-I · V30 |
|---|---|
| This body | Slot 2 is UHS-II. Slot 1 is CFexpress Type B. |
| Use | Fine in a UHS-I camera. Wrong bus for the R6 Mark III’s SD door. |
Keep a UHS-I Extreme PRO in another body. Put UHS-II V90 in this side door and CFexpress in slot 1, with a travel kit for this body in the bag — not a UHS-I card borrowed from an older Rebel.
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Frequently Asked Questions
Why CFexpress Type B on this body
Canon’s spec sheet puts CFexpress Type B, CFexpress 2.0 and VPG400 on slot 1. 7K Standard RAW at 29.97p is 2600 Mbps and the SD column is blank. B&H lists the same split: Type B up to 8 TB, SD UHS-II.
Whether 7K RAW can record to the SD slot
No. Canon marks Standard RAW and several Intra 59.94p rows as CFexpress-only. Slot 2 still handles 4K Long GOP (U3) and some Intra rates (V60 or V90 depending on the row).
Why 256 GB on slot 1 instead of 64 GB
Canon’s time table for Standard RAW 29.97p is 3 minutes on 64 GB, 13 minutes on 256 GB, 51 minutes on 1 TB. 256 GB is the travel size when that codec is in play. Cards over 2 TB also cannot run a firmware update.
Whether V60 is enough on slot 2
For stills and 4K Fine Long GOP, Canon lists U3. V60 includes U3. Intra High Quality at 29.97p lists V90; Intra High Quality at 59.94p has no SD option. The 12 fps RAW buffer on SD is 400 frames against 1000+ on CFexpress.
Whether a CFexpress 4.0 card works in the R6 Mark III
The camera lists CFexpress 2.0 and VPG400. A Type B 4.0 card is the same physical slot and falls back to 2.0 in camera. Buy on VPG400 and the 400 MB/s floor, not on the 3700 MB/s reader peak.
Final Verdict
For the EOS R6 Mark III, put SanDisk Extreme PRO CFexpress Type B in slot 1. Fill slot 2 with Extreme PRO UHS-II V90 when that door has to keep up, or 1800x GOLD V60 when it only sees stills and Long GOP. Leave UHS-I cards in UHS-I cameras. 7K RAW does not have an SD option.
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