How to migrate to 12-inch MacBook

Apple’s 12-inch MacBook is svelte and weights only 2 pounds. It also presents some challenges when migrating your data directly from another Mac.

All other Mac models since 2011 have Thunderbolt capability, meaning you can attach a Thunderbolt cable between the two computers, put the older computer into Target Disk Mode, and then use Migration Assistant on the new computer, which will see the old computer’s drive and copy from it.

The 12-inch MacBook has the same USB-C port found on current MacBook Pros and iMacs, but unlike those models, the port doesn’t offer Thunderbolt, so the method I just described doesn’t work. But there are still a couple of ways to do it. Make sure your 12-inch MacBook is fully charged before you start, since it won’t have wall power during the transfer.


Short version:

Via a hard drive: You can use migration assistant with a Time Machine USB external drive (or Time Capsule) as a source. You could also use Carbon Copy Cloner on your old Mac to copy its contents to a a USB external drive, and use that as a source for Migration Assistant.

Computer-to-computer: If you get a USB-C to male USB-A cable, and the old Mac is a 2012 model or later (meaning it has USB 3.0), you can go the other way. Erase the 12-inch MacBook’s drive; in that article, see the section “If you need to erase your startup disk,” about halfway down, and, for format, select APFS if the old Mac has High Sierra or later, or Mac OS Extended (Journaled) if not. Then put the new MacBook into Target Disk Mode, and use Carbon Copy Cloner on the old Mac to copy its entire drive, including the operating system, to the new MacBook. If the old Mac doesn’t have a current enough operating system to boot the new MacBook, you can start the 12-inch MacBook via Internet Recovery (command-option-R during startup), and reinstall macOS, which will upgrade the copied operating system. In the end, you’ll have gone computer-to-computer, despite the 12-inch MacBook not offering Thunderbolt connections.


Long, step-by-step version:

In any of the scenarios below, you’re going to want your new 12-inch MacBook to be fully charged, because you can’t have it plugged into the wall while you’re transferring. I’m also assuming the new MacBook has a drive that’s large enough to hold everything that was on your old Mac.

One option is to use an external drive that has a copy of your computer. If you have existing Time Machine backup on a hard drive, make the backup current by choosing “Back Up Now” from the Time Machine (backwards clock icon) menu at the top of your screen, eject the drive when it’s done, and then attach it to the new MacBook, using a USB-C to USB-A adapter. Or, if you have a Time Capsule, that’ll work too; just follow the same process to make it current (but don’t disconnect it) Either way, Migration Assistant will present your backup as a source to migrate from; if you’re doing Time Capsule over Wi-Fi, be prepared for it to take long time.

If you don’t have a Time Machine backup, or you don’t want to wait for a Time Capsule, you can get a hard drive and copy your whole computer using Time Machine or Carbon Copy Cloner (or, for much faster speed, use an external solid state drive like the Samsung T5).

But there’s also a way to go computer-to-computer, provided the original Mac is a 2012 model or later, meaning it has USB 3.0 ports. The general concept is that, rather than use Migration Assistant, you’re going to erase the new Mac’s drive, and copy the entirety of your old Mac, by using the 12-inch MacBook’s USB Disk Mode. You’ll end up with a clone, with the same operating system as the old Mac, on the new MacBook, and then you can upgrade it to the current operating system if you wish to, or if it’s necessary. Here’s the process:

  • You’re going to need a USB 3.0 or 3.1 USB-C to USB-A cable. Unlike the adapters Apple sells that have a female USB-A connector, this cable needs to have a male USB-A connector on one end.
  • Check the operating system on your older Mac by choosing About This Mac from the Apple menu. Then check the minimum operating system required on the MacBook, by visiting Ideally, the original computer has an operating system that is newer than the minimum. (So, for example, current MacBooks have a minimum operating system of 10.12.5, which means that your original computer should be on 10.12.6.)
  • If your Mac has an older operating system that won’t run on the MacBook, that’s OK, but when you copy over your system, you’ll need to immediately reinstall its operating system before you can use the 12-inch MacBook, as I’ll explain. Alternatively, you can update or upgrade the operating system on your old computer before you copy, but, as always, make sure you have a backup first.
  • Start up the 12-inch MacBook in internet recovery mode by holding down command-option-R immediately after you press the power button. If you don’t see a spinning globe, restart the computer, holding down the keys. If it takes, you’ll see the globe, and after a little while be asked to choose your Wi-Fi network. Do that, and then wait for the Recovery Disk to load. (We’re about to erase the internal drive, and I’ve had better luck using a High Sierra recovery disk to properly erase a disk that has the APFS file system on it.)
  • Once it loads and you get to the Recovery menu, open Disk Utility. Go to the View menu at the top of the screen and choose “Show All Devices”.
  • Click on the Apple SSD in the upper left of the window. On the right side, click the Erase button. Name it “Macintosh HD” if you feel like being traditional, or anything else you like.
  • Make sure Partition Scheme is “GUID Partition Map”.
  • For Format, If your old Mac has High Sierra on it, choose “APFS”. If the old Mac has Sierra or earlier, choose “Mac OS Extended (Journaled)”.
  • Click Erase. If you get an error, which is entirely possible due to bugs in Apple’s Disk Utility, just click the Erase button again, until it works. If it continues to bug you, click on “Macintosh HD,” then click Unmount, then try again.
  • Quit Disk Utility. Restart the computer, holding down the T key this time. If it takes, you’ll immediately see a large USB (trident) logo on your screen, rather than an Apple or anything else. If you don’t see this, you may need to force off the computer by holding down the power button for ten seconds, and try again.
  • Connect the USB-C to USB-A cable between the two computers. You’ll see your newly erased drive appear as a drive on your old Mac.
  • Run Carbon Copy Cloner on your old Mac to copy your old drive to your new drive. If you are copying a system that is new enough to run on the new machine, then elect to create a Recovery Partition when it asks. If you’re copying a system that’s too old, then decline.

When it’s all done, eject the 12-inch MacBook’s drive from the desktop on your old Mac, and turn off the MacBook by holding down the power button, and disconnect the cable.

If your old Mac had an operating system that is new enough to run on the 12-inch MacBook, you can now just turn on the MacBook, exactly as you would have on your old Mac. and you’ll be in business. If you want to update or upgrade it to the latest and greatest, you can do so from the Mac App Store, as usual.

You’ll probably need to sign in to and/or reactivate various services and software, such as iCloud, Dropbox, Microsoft Office, and cloud backup like CrashPlan or BackBlaze.