Can You Upgrade It?

Technically, you can upgrade the internal storage (SSD), but:

• The SSD is soldered to the logic board in many configurations, making upgrades extremely difficult or impossible.
• Only the Fusion Drive or HDD versions of some 2018 Mac minis might be upgradeable with special tools and expertise.
• Apple does not provide official upgrade paths for the internal storage.

What Are Your Options?

Internal SSD Upgrade (Advanced DIY)
This requires disassembling the Mac mini, removing the logic board, and possibly replacing or reflowing chips. It’s a complicated process requiring anti-static tools, a Pentalobe and Torx screwdriver set, and a high level of expertise. Attempting this may void your warranty or damage your device.

External SSD (Recommended)

A much easier and safer solution is to use an external SSD via Thunderbolt 3 or USB-C. Performance is nearly equal to an internal drive, and it’s ideal for booting macOS or storing heavy applications and files. Popular options include the Samsung T7, SanDisk Extreme Portable SSD, and Thunderbolt 3 NVMe enclosures.

Recommended: External SSD Boot Drive

Using an external SSD as your main drive offers a great balance of speed, safety, and convenience. Here’s how to set it up:

• Connect your external SSD using Thunderbolt or USB-C.
• Format it via Disk Utility.
• Install macOS on it using macOS Recovery.
• Once installed, go to System Settings > Startup Disk and choose the external SSD as your boot drive.

Conclusion

Internal SSD upgrades in the 2018 Mac mini are technically possible, but difficult and risky. For most users, an external SSD is the best way to boost performance, add storage, and extend the life of your Mac mini — with minimal hassle.

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