You shoot weddings, and a single event can fill a memory card and then a good part of your Mac's storage. Apple released macOS 27 on 14 September 2026, and before you update you want a drive that will hold a proper backup. This guide explains which drive to buy for Time Machine (the Mac's built-in backup tool), how big it should be, how to set it up, and why one backup is not enough for client work.
Which drive should I buy for Time Machine before macOS 27?
Short answer: Buy an external drive that is larger than everything on your Mac, and pick an external SSD (a fast drive with no moving parts) if you handle large photo or video libraries, or a portable hard drive if the backup stays on your desk and cost matters most. Use a new or empty drive, because Time Machine may need to erase it when it first sets it up.
Will macOS 27 run on my Mac?
Apple released macOS 27 Golden Gate on 14 September 2026, and it supports Apple silicon Macs only. macOS 26 Tahoe is the last version for Intel Macs. Apple also dropped some older models from the list, including the 2019 16-inch MacBook Pro, the 2020 13-inch MacBook Pro with four ports, the 2020 27-inch iMac and the 2019 Mac Pro. If you are not sure which chip you have, open the Apple menu and choose About This Mac. Some newer Siri features in macOS 27 need an M3 chip or later and 12 GB of memory, so not every feature will appear on every supported Mac.
SSD or hard drive for Time Machine?
If you already own a bare SSD, a case can turn it into an external drive. Our guide to a USB-C SSD enclosure for video editors explains what to look for in the case.
How big should the drive be?
Look at About This Mac, then Storage, to see how much your Mac uses. Time Machine keeps older versions of changed files, so choose a drive that is comfortably larger than the used space, as a rule of thumb at least double. For a busy photo library, bigger is better. Check the printed capacity on the box against the usable space, because a drive always shows a little less.
Check the port and cable
Newer Macs use USB-C or Thunderbolt ports. A drive with the right cable avoids adapters that loosen over time. A loose cable during a backup can make the drive disconnect; our note on an external SSD ejected unexpectedly on macOS explains the fix.
How do I set up Time Machine safely?
- Update nothing yet. Connect the new drive and close other heavy apps.
- Open System Settings, search for Time Machine and add the backup disk. The wording can differ slightly between macOS versions.
- If Time Machine offers to erase and format the drive, accept (a new drive has nothing to lose), then let the first backup run to the end. It may take hours, so keep the Mac plugged in.
- Open the backup in Time Machine and restore one small file as a test.
Do not unplug the drive during the first backup and do not begin the macOS upgrade until it has finished. Our guide on keeping Time Machine fast and reliable covers what to do once the first backup is done.
Power cuts, humidity and travel with your Mac
Power cuts and voltage dips can interrupt a long backup, so use a surge-protected socket, and if your Mac is a laptop, keep it charged. Humidity during the monsoon months and dust on location shoots are hard on exposed ports and drives, so store the drive in a closed pouch. If you travel between cities for events, remember that a Mac that has to travel by courier for repair is away for extra days, so keep your backup somewhere you can reach it.
When to get help
- Time Machine reports that the backup could not be completed again and again.
- The Mac does not show the external drive, or the drive makes clicking sounds.
- The Mac slows down badly, restarts by itself or freezes during the macOS 27 upgrade.
- You cannot reach photos you need for a client delivery.
Stop and contact us. Our Apple laptop service hub covers MacBooks and iMacs. In Hyderabad we visit you at home, and the charge is ₹149 doorstep visit fee, waived when you approve laptop repair with us. We also accept Macs by courier from anywhere in India. Quotes come after diagnosis and are shared for approval before any work.
A note from the LRW Engineer Team
Treat Time Machine as the safety net, not the archive. For finished client work, keep a second copy on a different drive or in cloud storage, and store that drive in a different place from your kit bag. When a gallery is delivered, copy it twice before you clear the cards.