Mac storage basics · External storage and adding space
Is an external SSD a good way to get more storage on a Mac?
Short answer: Yes. A USB-C or Thunderbolt SSD is fast enough to work from and much cheaper per gigabyte than a bigger internal drive; it just needs to be connected for what's on it.
Yes — for most people it's the most practical way to add space after buying a Mac. A good external SSD over USB-C or Thunderbolt is fast enough to work from directly, not just to archive to, and costs far less per gigabyte than a bigger internal drive at purchase.
The trade-off is that the drive must be connected for whatever lives on it. That's why a good setup keeps everyday essentials on the Mac and moves big, less urgent things — media libraries, finished projects, large apps, developer caches — to the SSD. Storage Studio is built for exactly that split. See choosing an external drive.