Memory Cards For Sony A7III – 27 Tested

The Sony A7III features a dual SD memory card slot configuration. Slot one can take V90 UHS-II cards, and slot two is limited to UHS-I cards. Because of this setup, picking the right memory cards can get tricky, and you must decide what cards to use when running two cards.

This guide will walk you through some great choices with in-camera benchmarks.

Sony A7III – Amazon / B&H

Recommended SD Cards for Sony A7 III

You will only need a UHS-I U3 card to shoot video as the camera has only a 100Mbps bitrate, even at 4k.

V90 UHS-II cards are best for running a single memory card set up with the maximum speed. The Sony A7III has good performance as long as you don’t use the second UHS-I memory card slot as a backup.

V60 UHS-II cards are a great compromise for speed and performance. They still run fast but cost a lot less.

Here are some of the best SD cards for the Sony A7III based on our in-camera benchmarks.

There are some new cards added to the list that I’ve found work well when testing memory cards for the Sony A7IV.
If I were buying cards today I would go with Sony G Tough or Sony M Tough in Slot 1, and Sony E in Slot 2. But only if I wasn’t shooting backup. If I were shooting backup with both cards, I would go with two Sony E cards.

Also, check out some of the Best Accessories For The Sony A7 III

I also keep an up-to-date list of Every Lens For The Sony A7 III

In-Camera Speed Test

This chart displays Sony A7III SD card speeds tested in the camera.

There have been a lot of new memory cards since I last tested the A7III, so with some cards, I just used the previous generation speed. It should be at least the same or faster.

For the tests, I shoot a continuous burst using uncompressed RAW at ISO 100 with a shutter speed of 1/100.

I also test each card to check for 4k recording compatibility. Sony cameras don’t like some cards. For example, many Samsung cards even though they are U3 and SDXC, get rejected by the camera with an error that they are not U3 cards.

Sony A7III Camera Specs Buffer Questions

Sensor: 24MP Full-Frame Exmor R BSI CMOS Sensor
Processor: BIONZ X Image Processor & Front-End LSI
What Size Is The Buffer? 1.5GB estimated
What Memory Cards Are Compatible? UHS-I / UHS-II
Max Memory Card Capacity: Up to 1TB or larger.
How Long To Clear Buffer? 9:36
How Many Uncompressed Shots To Fill Buffer? 46

UHS-II vs. UHS-I Memory Cards In The Sony A7rIII

While the Sony A7 III takes advantage of UHS-II memory cards, speeds will be bottlenecked to the slowest memory card in the camera depending on how you’re using slot 1 and slot 2 with the recording modes.

Recording Mode Standard | Slot 1 | Auto Switch On

If you’re using Slot 2 as an overflow, then you will get UHS-II memory card speeds in Slot 1 until the card fills up. Then once the camera switches to Slot 2, speeds will slow down to the speed of the card in Slot 2 and that slot will only be able to produce UHS-I speeds.

With the Sony A7III, Auto Switch is turned off by default, so you will need to enable this yourself to gain this benefit.

Record Mode Simult. RAW+RAW

If you’re shooting Slot 1 and Slot 2 as a backup, then memory card write speeds will be throttled to the slowest card. If you shoot like this often, you may not see any benefit to using UHS-II cards.

Record Mode Simult. RAW+JPEG

We no longer test RAW+JPEG, but since JPEG files are smaller, you don’t see the same bottleneck as when you’re backing up with RAW to slot 2.

However, shooting RAW+JPEG does slow down the buffer’s performance significantly. It requires more processing as the cards are written to, and this task is usually not multithreaded.

Shooting Uncompressed RAW will produce massive files and fill your buffer much quicker, but it won’t slow down your memory card write speeds.

What Size Memory Card For Sony A7III?

The Sony A7III can take memory cards of any size, from 32GB or smaller all the way up to 1TB or larger. You’ll want to start with a 64GB card to use the SDXC file system.

For Stills

I recommend 128GB.

For photographers shooting only still, I recommend buying a 128GB card. While I never use more than 128GB in a day of shooting, occasionally, I’ll forget to clear off my camera before going out to shoot again, and having the extra memory is nice.

Also, if you decide to record video, the 128GB cards will allow you to record without breaking the video files up into 4GB chunks since 32GB cards can only be formatted with a 32-bit filesystem.

For Video

The memory card size for the Sony A7III when recording video depends on your recording format and how you plan on using the camera.

There are a few details you should note. Take a look at the max bitrates.

4k 24p / 30p Max Bitrate: 100Mbps

1080 24p / 25p / 30p / 50p / 60p Max Bitrate: 50Mbps

To get the maximum quality or 100Mbps at 24fps or 30fps with the Sony A7III you will need to record in 4k unless you want  100fps or 120fps then you can record 1080p with 100Mbps.

If you only want 1080p 24fps or 1080p 30fps, you will only get half the bitrate of 50Mbps. So even if you need 1080p, it’s better to record 4k and then scale down, which, if done correctly in a 16-bit sequence, will result in a 4:2:2 sampling.

Maximum Video Record Times by Memory Card Size

Here is a handy chart you can use to find the best-size memory card for your recording format or to determine the number of minutes you can get with the different formats on different-size cards.

For video shooters and filmmakers, I recommend 128GB cards or higher. Now that there are 1TB SD cards available on the market, filmmakers who need to record a lot of video without the need to clear off their cards might find these larger cards useful.