Nintendo Switch 2 is only compatible with microSD Express cards which are significantly faster than the non-Express microSD cards used with Switch 1 or Steam Deck. With this new technology comes a higher price tag and a lot of speculation. We purchased six of the most common microSD Express cards, from both well known brands like Samsung as well as lesser known brands like NEXT, and put them through thorough testing to get the facts.

Our testing revealed that all the microSD Express cards performed about the same. Pick the size and price that makes the most sense for you. We track prices for all reliable brands. Here’s the lowest price for each size:

Ultimately, we want to know what microSD Express card is the best. To determine that we’ll answer a few questions:

We chose four popular Nintendo Switch 2 games to test: Mario Kart World, Star Wars Outlaws, Donkey Kong Bananza, and Cyberpunk 2077. For each game, we recorded loading times from microSD Express card, system storage, and directly from the game card (except Star Wars Outlaws, which is a Game-Key Card release). We tested each card at each storage size, and recorded the average loading time for each game.

For off brand cards, we compared the Manufacturer ID (MID) encoded on each SD card to a list of MIDs to determine the true manufacturer. Matt Cole's breakdown of SD card manufacturer IDs was an essential resource for us during this process.

During initial testing, we used open source software like Fight Flash Fraud and CrystalDiskMark to determine average sequential and random read/write speeds. The data provided by these tools were not always correlated to perceived loading times, so we decided real-world loading times were a better metric to measure.

Hardware used for testing includes:

Nintendo Switch 2 was built from the ground up with faster storage. Games with higher definition textures and audio require these faster storage speeds to function. Because of this, Nintendo Switch 2 is only compatible with microSD Express cards.

microSD Express cards will feature one of two logos: EXPRESS or EX

microSD Express cards are backwards compatible so if you do not yet have a Switch 2 but you find a great deal on a microSD Express card, you can still use that card in older devices.

Nintendo Switch 2 storage expansion options are rather limited (and expensive) but several options outside of well-known brands such as Samsung and SanDisk have surfaced. Are these cards reliable? Who actually manufactures these cards? Are these cards worth buying? We ran technical tests on each brand to find out more.

Skeptical of their much lower prices, we purchased onn, NEXT, and GameStop microSD Express cards so that we could investigate for ourselves. What we found is... mostly unsurprising.

Unmasking the True SD Card Manufacturer
Information is encoded on SD cards when they are produced such as product name, serial number, manufacturing date, and most importantly for us: manufacturer ID.

A Manufacturer ID (MID) is assigned to a manufacturer by the SD Association. This information is considered confidential, so there is no official list published anywhere, but some savvy nerds have diligently worked to compile lists of MIDs and companies.

Matt Cole's breakdown of SD card manufacturer IDs was an essential resource for us while researching the true manufacturer for onn and NEXT branded microSD Express cards.

system_profiler SPCardReaderDataType
With this one command (and Matt Cole's table of MIDs), we're able to quickly identify the real manufacturer of both onn and NEXT branded microSD Express cards: Longsys, a Chinese semiconductor company who purchased well-known SD card brand Lexar in 2017.

Here's the raw output from my Mac:

The important bits? Product Name: LSUSD00 and Manufacturer ID: 0xad.

As best anyone can tell, LS in the product name stands for Longsys and 0xad is their MID.

In summary? Whether you go with an onn, NEXT, or GameStop-branded microSD Express card, you're going to end up with a card manufactured by Longsys / Lexar, a trusted brand.