The Best SD Card For Sony A7III

Best SD Card For Sony A7III

Choosing the best SD card for your Sony A7III can be a daunting task.  With the vast amount of cards on the market, choosing the correct one for you is very important.  

Well, you’ve come to the right place.  This article is going to cover the different brands of cards and which ones are best.  It will also include why data rates matter and which speed best works with the A7III.  Lastly, we will go over which brands and data rates you should avoid.

By the end of this article, you’ll be much more confident in purchasing the best card that will work for you.

Without further ado, let’s dive in!

A quick look

I thought it would be fitting to link the different card here, as an overview of what's to come.  Feel free to click on them to be taken over to Amazon for purchase.  We highly recommend to scroll down and read the information to ensure you are purchasing the correct product for your needs!

SD card brands that matter

Best SD Card For Sony A7III

When you search the web or major online e commerce websites (like amazon), you’ll see tens of hundreds of different brands sellingSD cards.  More apparent are the price differences.  Without going into too much detail about why the prices are so different (we will get more in depth with this later), there are various reasons why the prices are so different.

What I will say in this section is the fact that some manufacturers cut corners when it comes to the quality of their cards.  More importantly, manufacturer's cut corners in reliability.  Reliability is one of the most important aspects of a memory card.  It should be your top priority.

I understand price can be a major factor in any purchase.  We all try to get the best bang for our buck (I know I do) - but when it comes to reliable brands, these are the brands that will not let you down:

  • Sandisk
  • Sony
  • Lexar

There are a couple other very reliable brands including Kingston and Patriot - but they don’t offer data rates fast enough for your A7III at this time.

Rest assured, if you stick with these three brands, you won’t have an issue with losing your data.  Don’t get me wrong, things happen and there are no guarantees that you won’t lose your data when using one of these cards. These brands have a very low fail rate.

Let's move onto data rates.

Best SD Card For Sony A7III

Kingston data rates aren't fast enough for the A7III

Why SD card data rates matter

Best SD Card For Sony A7III

This photo shows the data rate of 1080p (120 fps) and 4k (24 fps) is 100MB/s (which is what 100M means).  This is the recommended settings for the best visual result.

This is the section that I like to discuss with people the most when they ask me which card they should buy.  It’s quite easy to wrap your head around when it’s explained clearly.

For one, the Sony A7III records video at a maximum of 100 megabytes per second (mbps).  That’s a pretty significant amount of data per second.  That is where the data rates on your card come into play.

When it comes to the A7III, you’ll want to have a card that it capable of being written to at 100mbps.  This will guarantee that the data the camera is attempting to write, will be allowed to written to that quickly.

When shooting continuous photos (7+ per second), you’ll notice the buffer time writing to the card will be shorter the faster your card is.

You would not want to purchase a card that writes less than 100mbps.  The camera would write to a card that’s a lower data rate. But, you have a very high chance of having corrupt files in the process. Technically, you wouldn’t have to purchase a card that’s more than 100mbps.  This is where I enjoy educating people. 

Best SD Card For Sony A7III

This G series Sony SD card writes at 299 MB/s and Reads at 300MB/s.

Purchase a card the writes faster than the minimum requirements

My recommendation is having a card that can write faster than 100mbps. Why? Because you aren’t bottlenecking the card on a consistent basis.  This will lead to a longer lasting card that isn’t being worked to its maximum every time it’s being used.

You could say this about anything in life really.  Let’s take a pickup truck for example.  If It’s able to tow 10,000 pounds, I’m hoping you wouldn’t load it with 10,000 pounds.  You would load it slightly less (like 8,000) pounds so the truck isn’t working so hard.  If you really needed to carry 10,000 pounds, you would hopefully upgrade to a larger truck (or do it on rare occasions).

Lastly,  be sure to check the write speeds.  The number that is typically displayed on a card are the read speeds.  Rarely do cards display the write speeds along with them.  Typically, you have to dive a bit deeper in the description or on the packaging.  Read speeds are important, write speeds are far more important.

Best SD Card For Sony A7III

The number in the red box indicated read speeds, not write.  A little additional research is required to determine that (normally write is lower than read).​​

To recap this section:

  • Sony A7III captures at a maximum of 100mbps 
  • Check the write speeds
  • Do not purchase a card less than 100mbps
  • Purchase a card above 100mbps (preferably 150mbps)

Don’t skimp for cheaper cards

This is self explanatory, but seeing as you have purchased (or will purchase) the A7III, lenses, extra batteries - do not skimp and buy a cheap card.  The card is what is going to hold all of the information that you’ve captured with all of the equipment you have spent your hard earned money on.

You have purchased quality equipment thus far (the camera, lenses, etc) - continue the quality purchases by continuing to read and buying a quality card that I recommend.


This is a debatable question.  First, UHS-II is faster, period.  Is it more reliable?  I have nothing to show that it is.  In my personal opinion, they are both equally reliable.

As far as which one to choose, I choose UHS-II.  Let me explain.

There aren’t any cards on the market in the UHS-I class that can write at 100MB/s.  They get close (90-95MB/s) but it doesn’t meet or exceed the 100MB/s requirement.  

While card slot 1 only supports UHS-II (the second slot is UHS-I) - the cards that I'm recommending are compatible with UHS-I and UHS-II card slots.  They will work in both without a problem.

The marking in the white box indicates what UHS class it's in.  This version is a II.

Which size SD card you should purchase

This is an example of 128GB versions.  There are other versions in the UHS-II line of cards including 32, 64, and 128GBs.

There are a few questions you need to ask and answer yourself.  These questions are

  • How much video are you going to be shooting
  • How many photos are you capturing at one time
  • How often are you able to offload data
  • How much are you able to spend

With file sizes getting increasingly larger, there is a need for larger cards.  I’m not doubting or saying large cards should exist.  Take for example, this weekend I took a small vacation to New York City. I took my A7III with me.  I shot 140 photos, uncompressed raw and extra fine JPG.  Those 140 (280 total with raw and JPG) photos ended up being nearly 9 gigs.

What I am getting at is, while file sizes may be much larger, you may find yourself not needing the largest 256gb card.  You may be wasting money if you go that route.

If you find yourself being able to off-load your photos often ( I was able to off-load halfway through the say), you will not need 256GB.  You won’t need 128GB either, most likely.  On days I know I’ll be able to offload, I'll use 2 64GB cards.  

The same can be said about shooting video.

I don’t shoot redundant either.  I have that much faith in my memory cards.  I set the camera to record completely to slot 1 and then move to slot 2.  So in theory, I have 128gb cards.  This will easily give me a solid 70+ minutes of video.

This is an example of my 140 photos (280 total with JPG and raws).  There are small lightroom files in there as well from editing.  Total of nearly 9 gigs of data.

If you truly find yourself shooting more than 70 minutes of video before offload - by all means, purchase something larger.  I wouldn’t want you to make the same mistake I did (spending $400+ on two 256GB cards and not really using them).

Let’s move into the cards themselves!

Sandisk is the brand that’s a bit tricky when it comes to choosing the best card for a Sony A7III.  The reason being, their write speed variations.

Sandisk offers a UHS-I card that writes just under the 100MB/s requirement.  The specific number is 95MB/s.  You can get away with using them.  I have used them from time to time (when I have forgotten my card in the card reader).  They have worked.  But my work is worth so much more than a slightly higher cost of a card.  The card will pay for itself easily over time.

What I recommend is purchasing the UHS-II 300MB/s cards.  This exceeds the 100MB/s requirement, and more.  You’ll get very good performance out of it and it’s worth every penny.

There are many versions of this card, including:

Remember what we discussed earlier - the size of the card depends on your workload.  Don’t waste your money on more store than you’ll need.

Speed is worth everything

If you have ever used a UHS-I card, and upgraded to a class II card - you’ll notice a difference immediately.  Write speeds within the camera is faster (less buffer time) and your workflow when you get home is faster as well.  Transfers from the card to your computer will be noticeably faster.

This speed is worth money too, when you think about it.  If it writes, reads, and transfers faster - your entire workflow will be faster.  This will allow you to do more in the same amount of time - essentially making you more money.

I will leave a link here to the less expensive cards that are reliable.  But I would highly recommend to upgrade in the future when you are able.  I wouldn’t want to see or hear that your files ended up corrupt because of a slow card.  Keep that in mind.

Let’s move onto the Lexar’s

Avoid this version.  The read speeds are great - which is misleading if you don't do your research.  The write speeds are too low to be completely reliable.

Lexar has a pretty decent reputation over the years.  They aren’t mainstream like Sandisk, Sony, or Kingston - but this reflects in their very competitive pricing.  

When looking at Lexar on various E Commerce websites (like amazon) - their read speeds are great and affordable.  They have a 250MB/s card that’s priced great.  What they don’t claim is their write speeds.  You have to do some additional digging to find their write speeds on those specific cards.  Refer to the image to the right (or below on mobile).  It only has a write speed of 90MB/s.  I do not recommend this specific card.  

The 2000x model card is the professional version that is recommended.  It will write at 260MB/s.  Far exceeding the A7III’s write speeds. 

Let’s move onto Sony

Sony has a great reputation in the electronic industry.  I mean, you have an A7III - that should say enough right there.

When it comes to their SD cards, I’ll admit - they are a bit expensive.  From my calculations, they are roughly 30% more than a Sandisk and Lexar.  Don’t let that discourage you though, it is Sony. They are reliable and offer quite a few variations in data rate as well.

The reason I chose to recommend the 100MB/s version is the fact that the tests on the card read slightly higher for those who have tested them.  I won’t post the tests seeing as I didn’t do them myself, but you can do the same by searching for the results.

Sony does offer a 150MB/s version, but in a 256GB card.  The card is double the amount of data and 50% higher speeds while writing for an additional 30%.  The 256GB version is a steal. The only reason I didn’t recommend it is because not everyone needs that much space.  Again, I wouldn’t want you to purchase something that you didn’t need.

Sony A7III recording video card

I mention this to a lot of people I have talked to when recommending products that I use.  I recommend an SD card and a card reader to go along with it.

The thing is, when you get into higher data rates and very large files, if you don’t have a card reader that’s at least a decent speed - it can take a very long time to transfer files.

Take my experience for example.  A few years ago I was transferring video from my UHS-I card on my laptop from footage I had taken on my Canon 80D.  I had just purchased the camera and took a lot of slow motion / 60fps footage. I had filled a 64 GB card.  

Transfer times from an integrated card reader took forever...

Transferring the data on my laptops built in card reader took a little over 25 minutes.  Yes, 25 minutes. This wasn’t an old laptop either (I believe I had purchased it 6 months prior).  It’s an example of purchasing something that is dedicated at doing a single task. The card reader that was built into the laptop was enough for the average person to get by with.  But when transferring large files, it just didn’t cut it.

Between the two cards, I believe I spent 40 minutes waiting for all of the footage to transfer.  That was 40 minutes I could have been editing. I immediately purchased a dedicated card reader and haven’t looked back since.

As video files, extra fine JPG’s, and uncompressed RAW files get larger, your overall data usage will increase.  You will need a card reader to save you time. Time is money.

I always recommend ProGrade card readers.  I have been using this particular model for about a year and a half - and couldn’t be happier.  I couldn’t recommend this card reader more.

The SD card brands to avoid - like the plague

For me, and this is personal, I can always tell a beginner or amerture from an intermediate/advanced shooter when I look at their memory card.  I mean, there isn’t anything wrong with using these brands that I’m about to mention - everyone has to start somewhere. But when those same people come to me and talk about how their card corrupted during a shoot - I tell them to stop buying cheap unreliable cards.

The major brand to avoid is Transcend.  This is a common brand that comes with “kits” or “bundles” from places like amazon.  The data rates are terrible and their reliability is even worse. When I started shooting with a DSLR, this is the brand I started with.  The card ended up failing when attempting to record video (at 1080p on a Canon T6, really?!!?)

The other brand to avoid

The second brand you need to avoid like the plague is Delkin Devices.  Good Lord, have I heard horror stories from this brand. A little backstory, I belong to a few great Facebook filming and photography groups.  I can’t tell you how many people in the filming groups that have had their Cfast cards fail (their SD cards are equally as bad).

I know of one guy that shot an entire wedding and brought the footage home to find the entire card was corrupt and it was unrecoverable.  There was another person that attempted to record at 4k on a 1DC mark II and the card kept stopping him from recording about 5 seconds into shooting. Why? Because the data rates on the Cfast card was false. He ended up getting reimbursed.  

Long story short, if the card is cheap and seems like it’s probably too good to be true… it is.  Stay away from the off-brands you’ve heard nothing about. Don’t always trust the reviews on Amazon either, they are cracking down on all of the fake/paid reviews.

Stick with the major brands, you’ll thank yourself for it.

Sony A7III recording video card

Avoid this brand at all costs.  Don't let their low prices fool you - they're cheap for a reason.

Let’s wrap it up

Let’s do a little recap of what we have covered today.  If anything these are the things you should take away from this article.

  • Stick with major brands (Sandisk, Sony, Lexar, etc.)
  • Don’t buy cheap
  • UHS-II is faster than UHS-II (which is what you want)
  • Shoot for 100MB/s (it’s possible to use 90MB/s but plan to upgrade when you can)
  • Choose a size that best fits your needs
  • Purchase a good dedicated card reader (it’ll save you a lot of time in the long run)

One you understand the difference between cards, it becomes quite easy to decide.  I really hope this article did just that for you.

If you would like more recommendations of other products, be sure to check out our camera gear section. We also have a beginners guide section that you might be interested in as well.

As always, thank you so much for reading.  Until next time, keep shooting!



Giving credit where it's due.


I have been taking photos and film since I was a child. Now that I'm in my mid 30's, I want to share with the world what I have learned over the years. I attempt to live every day to the fullest and share that with you through my blog. I am an electrician by trade and photo and video lie within the "hobby" aspect of my life at the moment. It's what I'm truly passionate about.
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