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The Best SD Card For Sony A7iii

Published On:
July 28, 2021
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Choosing the right SD card for your Sony a7 iii can be a daunting task. There are so many options out there and it's hard to know which one is best for your needs.

We'll walk you through the different types of memory cards available, what they mean, their speeds, and give you our top recommendations.

This article will help you choose the best SD card for Sony a7iii without wasting time or money on something that doesn't fit your needs

Let's get started!

**Note: This article was updated on January 14th 2022 to include, video bitrates along with the reason it's so important, the SD cards mentioned can be applied to photography as well, and cleaned up a few sections to allow for a better flow of the article**

The SD Cards At A Glance

I have included a table below that lists each card on this list.  I highly recommend reading the rest of the article to understand why I have recommended them.  I have included UHS-II card readers as well.  UHS-II card readers are required to harness the UHS-II speeds.

SD Cards

SD Card
R/W Speeds
UHS Type
90/170 MB/s
120/160 MB/s
100/260 MB/s
299/300 MB/s
130/250 MB/s
hello world!

SD Card Readers

Card Reader
Max Speed
BUS Type
USB Type A
300 MB/s
USB Type C
300 MB/s
USB Type A & C
1.25 GB/s
CF Express B And UHS-I & II
hello world!

Most Important Aspect Of An SD Card (For Photo And Video)

Let's be honest here - any digital artist's worst nightmare is losing their work. I can't tell you how many people I have talked to both personally and in groups/forums that ask how to recover data off a memory card.

You can say that it happens to the best of us - and it'll eventually happen to everyone. While this may be true - taking as many preventative measures as possible, is very important.

The first (and most important in my opinion), is a reputable brand. While you may pay less upfront for a cheap SD card, you can end up paying far more in time, reputation, and overall work by doing so.

Reliability Is More Important Than The Memory Cards Size Or Speed

Look, everyone has a budget. I get it. There are very few out there that can throw around money and get the best of the best.

With that being said, if you find yourself debating whether to get sd cards that are larger versus ones that have been known to be more reliable... please, do yourself a favor and go with the ones that are more reliable.  Shortly, we will discuss the most reliable brands on the market today.

But before we get into that - let's discuss data rates and why they're so important (when it comes to SD cards for the A7iii).

Bitrate Of The Sony A7iii (And Why It's So Important)

Frame Rates
Bit Rate
100 Mb/s
100 Mb/s
100 Mb/s
50 Mb/s
50 Mb/s
50 Mb/s
hello world!

Refer to the chart above if you're wondering what the Sony A7iii bitrates are.  Please note that there is a 4k 60Mb/s option as well. Not many people use it since it's lower in quality - but it can save you space on your card (allowing you to record for longer periods of time).

The reason bitrates are so important is actually pretty simple to understand.

Bitrate is the rate at which your device writes data to your SD card.  Generally speaking, this is represented in seconds.  For example, 50 MB/s would be a bitrate of 50 Megabytes per second.  This means your device would be writing 50 Megabytes worth of data every second to your card.

I'm sure you can see why this would be so important.  Every card on the market doesn't write at the same speed or execute this process reliably over a long period of time.  Cards that are too slow tend to corrupt - as the card is being overloaded with data requests it can't keep up with.

Keep this topic in mind as we move on to the difference between MB, Mb, and MB (equally as important).

The Difference Between MB, Mb, And mb

This is a topic that many people either don't know about or overlook altogether.  Most people I've talked to over the years assume that everything means MB/s (or Megabytes per second).  This is not true at all.

It should be noted that there's a major difference between each of these acronyms.  These differences are:

  • Mb (or mbit) is a : Millibit
  • Mb is a: Megabit
  • MB is a: Megabyte

The conversion of each is pretty simple - but the size difference is vast.

To put this into scale - A megabit is 8 times smaller than a megabyte.  So it takes 8 Mb to equal 1 MB.

On the other hand - a millibit is 1,000,000,000 times smaller than a megabit.  So, it would take 1,000,000,000 (a billion) millibits to equal one Megabit - or 8,000,000,000 millibits to equal one megabyte.

This is quite a difference, wouldn't you say?

So Why Are These Numbers So Important?

Simply put, you may only need a slower (or faster) card than you may have expected.

If you reference the bit-rate chart from above again, you'll notice that all of the rates are in Mb/s.  Again, that's Megabits per second.  

Seeing as there are 8 Mb per MB (and all SD cards are advertised and rated for MB/s) - you wouldn't need a card that's rated for 100 MB/s if you're shooting in 4k on the Sony A7iii.

If you do the math and divide 100 by 8 (100 Mb/s by 8 Mb per MB) - your requirement is 12.5 MB/s

  • 100/8 = 12.5

The Sony A7iii writes (in 4k) at 12.5 MB/s (which is 100 Mb/s)

Note that every card on this list far exceeds the 12.5 MB/s write speeds.

Speed Requirements For Sd Cards (For Sony A7iii)

Even though we just went over this briefly - take note of the image above.  This is what the menu looks like when you're changing bitrates of different resolutions within the A7iii.

The M after the number represents Mb/s (Mbps). The number before the p represents frames per second (fps).  So, each option from the image above would equate to:

  • 60fps/50Mbps
  • 60fps/30Mbps
  • 30fps/50Mbps
  • 30fps/16Mbps
  • 24fps/50mbps
  • 120fps/100Mbps

The MB/s requirement for each of the bitrates would be (again, divide to Mbps by 8)

  • 50Mbps = 6.25 MB/s
  • 30Mbps = 3.75 MB/s
  • 16Mbps =  2 MB/s
  • 100Mbps = 12.5 MB/s

I'm sure you get the drift at this point.  Understanding the difference is very important.

Memory Card Size Limit On The A7iii

If you didn't know already, there's a size limit on both memory card slots.

That limit is 256GB.

So, the max each slot can have is 256GB - for a total of 256GB (if mirroring) or 512GB (if running them separately).

UHS I Cards And UHS II Card - Which Is Which?

Before we move into the cards themselves - I thought it would be fitting to let you know that either slot isn't identical.

  • Card slot 1 is the fastest slot that supports UHS-II cards.
  • Card slot 2 only supports UHS I sd cards.

I'm sure Sony had their reasoning behind only supporting UHS-II in slot 1 (probably cost) - but it would have been nice to have both slots UHS-II.

If you take a look at the image below - you'll see on above the card slots (on the card door) it shows what each slot it compatible with.

I'm sure Sony had their reasoning behind only supporting UHS-II in slot 1 (probably cost) - but it would have been nice to have both slots UHS-II.

Slot one is backward compatible with UHS I (both slots can use UHS I cards)

So, keep that in mind going forward. If you plan on getting the fastest card - consider getting the fastest UHS I card (I'll explain here in a minute when you should consider it).

The Difference Between UHS I And UHS II Cards

The main difference between the two types of cards is not physical size, size of the card (memory), or even reliability...

It comes down to write speed.

UHS II is significantly faster than its counterparts. You'll notice on the card itself - it has a second row of pins... allowing on average almost double the transfer speeds of a regular UHS I card.

This is also why a UHS-II card will not work in card slot 2 on a Sony A7 iii. The slot itself isn't built to read/write to the second row of pins (that are seen on a UHS-II card).

Note: while the write speeds from the Sony to the card may not increase all the much (about 30%) - it's the transfer speed once you get home to offload. Your card reader won't be hindered nearly as much by the card itself in transferring large files (which is normally the bottle-neck).

This will allow you to transfer 3x+ faster than with a UHS-I.

Note: General consensus across all cameras and sd cards are that UHS I is perfect for those taking stills and UHS-II cards are geared for those taking video (and need to offload large files quickly). This makes sense but isn't something you have to follow. UHS I cards do just fine with video too, so don't worry.

Which UHS Version Should You Use?

It's pretty simple really (and for you to decide)... If you're running dual cards and mirroring them both - the speed at what the camera writes will be hindered by card slot 2.

Your slowest card will be your fastest card, in theory.

Now, there is nothing wrong with purchasing one of each type for the added benefit of high transfer speeds once you get home and off-load...but having identical cards across the board (especially when mirroring), just seems right to me.

The Most Reputable/Reliable SD Card Brands On The Market

Now, let's talk about the brands first before we move into the cards themselves. We believe building trust in a brand first, is just as important as receiving a wonderful product.

So, the way that we've come up with the most reliable/reputable sd card brands is:

  • The companies reputation (as a whole)
  • Reviews on a wide variety of memory cards that they offer
  • Personal experience (4+ years in the camera industry - 10+ years in the memory card industry)

With that being said - these are the most reliable brands on the market today.

  • Sandisk
  • Prograde
  • Lexar
  • Sony

I thought it would only be fitting to include brands to completely stay away from. This is due to negative reviews, poor craftsmanship, terrible customer service, and very poor reliability.

The brands to completely avoid:

  • Transcend
  • PNY
  • All 'off-brands' on amazon

Let's Move Onto The Best SD Card For Sony A7iii

Now that you understand a bit more about the card slots, different type of cards, and their benefits... let's move on to the cards themselves. Like mentioned earlier in the post - We're recommending 5 different memory cards for your Sony A7 iii - it's totally up to your needs about which one is best for you and your demands.

Let's get going!

SanDisk Extreme PRO UHS-I 128GB SDXC

First off, I personally own 10 (or more) of these.

I've never had a single one fail.

This is a UHS I card.

I have shot plenty of 4k video on this card. I run the exact same card in both slots (mirror mode). So, if one card did fail, the other would most likely save me.

With that being said - I've put over 70k actuations on my A7iii in the last 2 years. I've had two of these in my camera the entire time.

Transfer speeds, once I bring them back home, are pretty decent. Using an external card reader - I can transfer 1000 RAW files (about 50GB) in about 6 minutes. That comes out to 8.33GB per minute or 139 MB/s.

I know the card claims 170MB/s - but, not every card is the same, and a margin of +/-20% isn't too bad at a $35 price point.

The reason I don't have the 256GB versions is that I would never need that amount of space. It would be a waste for me - and having a bunch of the same card allows me to stay more organized (swap cards for different shoots).

There are 64GB and 256GB versions as well.

Lexar Professional 1066x 128GB SDXC UHS-I

Lexar is a solid brand. It's a shame they don't have the reputation that Sandisk does... but I get it, Sandisk is king and will probably remain that way for many many years to come.

The reason this card didn't make the top of the list is that I haven't had as much time to test and strain the card.

I've owned 4 of these for the last year and wrote about 7500 raw files to them (in total, not each).

But, I can say that you'll be more than covered for both photo and 4K video with this card (and it's cheaper than a Sandisk).

The transfer speeds are about the same as the Sandisk with +/- 5% in comparison.

You can't go wrong with Lexar. A top-quality brand with products to back them up.

They have 64GB and 256GB versions as well as a 128GB+Card Reader. The card reader is of good quality - transfer speeds up to 312 MB/s with a standard card and 160MB/s off a micro SD card.

Sony M Series SDXC UHS-II Card 128GB

First off, this is a UHS-II card.

I recommend it because it's the most affordable UHS-II card on the market (that's actually reliable).

The reason for this recommendation is the transfer speed.

As you can tell, the write speeds are pretty low for a UHS-II card. They do this to offer the card at a reasonable price and for those who want the added benefit of high transfer speeds but don't need high write speeds (like photographers).

All Sony cards include:

  • Water and dustproof
  • Temperature proof
  • X-ray and magnet proof
  • Recovery Software included via download (no additional charge)

With this being a Sony card - you'll be running a native sd card in your camera. This is only a good thing seeing as most manufacturers' products work the best with their own.

Seeing as it's a UHS-II card, I would recommend picking up the Sandisk Extreme Pro UHS-I 128GB version, as your second card. It's the first card we recommended on this list.

Also, it's highly recommended that you pickup a UHS-II card reader (if you don't have one already). You won't benefit from UHS-II speeds if you don't.

Here is a great affordable Sony card reader that will take advantage of the faster cards.


This is the fastest and most affordable card on this list (when comparing speed to price).

Yet, the smallest in size.

This is the trade-off.

So, this is perfect for recording video, uncompressed raw files, video files... anything that you can throw at it really. These are Sony's tough cards, and they're priced as such.

There's only 64GB on the card and you won't be able to use another in the second card slot (just like the one above). Remember, the second card slot is only UHS-I.

The benefits of this card are the same as the card above (with durability and benefits) - but it's just rated for much higher speeds.

Seeing as it's a UHS-II card, I would recommend picking up the Sandisk Extreme Pro UHS-I 256GB version, as your second card. It's the 256MB version of the first card recommended. It'll treat you just right.

Prograde UHS-II 256GB Card V60

Last but certainly not least is Prograde.

I have used prograde in Non-Sony cameras for 3+ years.

Never had a single one fail.

Read/Write speeds compared to the price is very reasonable.

Anti-counterfeit protection - they etch a unique serial number onto each of the cards. You can check this number through their website to make sure the card is authentic (you'd be surprised how many people sell fake SD cards of major brands).

You may think the read speed is a bit low for it being a UHS-II card... but it's really not.

Unless you're recording at a super high bit rate (like an EoS R) - there isn't a need for write speeds over 120 MB/s. This is perfect for the Sony A7iii.

Not only that - you're getting 256GB of storage... all for just over $100. You're getting a crazy deal here.

Not to mention the brand themselves stands behind every single card they make (hence the reason for the etching for counterfeit).

I recommend this card to a lot of people - and a lot of people turn away from it because of the cost... but it's cards and companies like this that keep you shooting. Who knows, you could be using this same card 5 years from now (a buddy of mine's has lasted him over 3 years now, or 100k+ files).

If you decide to get purchase it, do yourself a favor and pick up their card reader. Super small, durable, and will last forever. Transfer speeds are on point too, of course.

Seeing as it's a UHS-II card, I would recommend picking up the Sandisk Extreme Pro UHS-I 256GB as your second card. It's the 256MB version of the first card recommended.

That About Covers It!

Normally I would say that I would continue to update this article as time goes on to keep it fresh and to 'stay up with the times'... but seeing as the A7III's times about running out (not that it won't continue to be a great camera) - and UHS-I technology is going to be obsolete (one of the biggest drawbacks of the A7III)... this will probably be the last time I update this article.

But, you should have a much better idea now of what Sony's data rates are, what the difference between UHS-I and UHS-II are, and ultimately which card is going to work the best for you!

If you have any questions, please feel free to drop us a line through our contact page or shoot us a message on Facebook or Instagram. We LOVE hearing from our readers!

You can learn a bit more about us and what drives us in the business of photography.

It's been fun! Until next time, be safe and keep learning and creating!


What SD card do I need for Sony A7III?

A standard SD card up to 256GB. Both card slots are rated for UHS-I, but slot 1 is the only one compatible with UHS-II speeds. Sandisk, Prograde, and Sony (regular or Tough) are all recommended brands.

What memory card does the Sony a7 III use?

The A7III uses standard form factor SD cards with full SDXC format support. Slot 1 on the A7iii supports UHS-II speeds (up to 300MB/s), while slot 2 only supports UHS-I speeds (up to 104MB/s - theoretical, there are UHS-I cards that perform higher). Slot 1 is backwards compatible with UHS-I (meaning both slots accept UHS-I)

Which SD card is best for Sony a7riii?

This is somewhat debatable. Much like the somewhat inferior A7III, the RIII supports UHS-II speeds, but only in one slot. Standard SD card form factor works in both slots. SDXC format supported. We recommend Prograde in slot 1 (UHS-II) and Sandisk (of the same size) in slot 2 - mirroring each other.

Is 64GB enough for A7III?

That answer depends entirely on what you'll be shooting, how much of it you be shooting, and how often you'll be able to offload that data. It's totally enough if you're able to offload when you need to, or you don't shoot all that much. It's also more than enough if you'd rather purchase a bunch of them and swap them out when they get full (and offload a bunch of them later). I used to use 64GB cards only - for organization purposes. They're also pretty inexpensive and easy to swap out and keep track of.
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