Partition Seagate Backup Plus Title Image

So you want to whip your Seagate Backup Plus into shape. Partition shape.

You’ve a large Seagate Backup Plus and partitioning it is just the thing.

You can then have different sections of the drive so that you can store exactly what you want where you want.

Set it up so perfect so that you love this external hard drive even more on your Mac.

Seagate Backup Plus Slim 1TB Red

Click on the picture.

To take a look at a Review post

on the Seagate Backup Plus Slim

How To Partition Seagate Backup Plus On Your Mac

And for your Mac to use.

As long as you’re using the Mac operating system Sierra or above the steps I show you below are fine for you.

Previous releases of Mac OS may have slightly different screens. But the instructions written here will be just as good for you.

Before you start, first have your Backup Plus portable drive formatted as HFS+.

This means that you’ve bought the Seagate Backup Plus Slim. Or Seagate Backup Plus Portable. You can buy both these drives in HFS+ format.

If you’ve an NTFS or ExFAT formatted Seagate Backup Plus drive you’ll need for format it first to HFS+. It’s easy and only takes a few minutes. You’ll find out how in my article “How to Format Seagate Backup Plus for Mac Help. Don’t Freak Out“. Just follow the link.

Then head back here afterwards.

1. Power Up Your Mac And Log In.

Then plug in your Seagate Backup Plus. The drive gets its power from its USB cable. So be sure you’ve a charged up battery on your MacBook or MacBook Pro. Or plug yourself into external power. 

You really don’t want the power going part way through partitioning your backup plus.

2. Start Up The Disk Utility Software On Your Mac

Disk Utility is the software program that you’ll be using to do your partitioning. Disk Utility comes as part of your Mac’s operating system.

You can find Disk Utility by opening up a Finder Window. Click on the Application folder. Then you type disk utility into the search window.

Next choose the Applications folder for your search.

Then double click on Disk Utility to start it up.

The arrows in the picture below show you where.

Finder Window Search For Disk Utility
Finder Window Search For Disk Utility

3. Pick To Partition Your Seagate Backup Plus Drive

On the left hand side of the Disk Utility window you’ll see all the drives connected to your Mac.

You’ll find your Seagate Backup Plus hard drive listed under the ‘External’ heading. It’ll show as the name you gave the disk drive if you’ve formatted it.

Seagate Backup Plus Internal External drive list
Seagate Backup Plus Internal External drive list

Click on your Seagate Backup Plus drive’s name where you first see on the list.

Seagate Backup Plus List Arrow

You find this important. Click on your Backup Plus at the top level. You’ll have all sorts of problems. Including not being able to partition the drive if you click on it at the second level.

After that look at the top of the Disk Utility pop up window and click on Partition.

Select Partition
Select Partition

You’ll now have in front of you the partition window. Here you set how you’ll shape the backup plus for your Mac. You set here the number of partitions. And the size of each partition you want.

Seagate Backup Plus Partition Pop Up Window
Seagate Backup Plus Partition Pop Up Window

You can think of your Seagate Backup Plus right now as like one large cake.

The large circle on the screen shows your backup plus drive as one lump of cake. Or in computer speak, one large partition.

And now you’re going to split it up into different sections. Each section is a different partition.

4. Create Your Partitions On Your Seagate Backup Plus

The first thing for you to do is to type in a name for your first partition.

Type in a name that help you understand what that partition is for when you see it on your Mac’s desktop.

Then you set the format for the partition using the up down arrows. The arrow on the picture above shows you where.

  • For a partition you want to copy and paste files to. Or drag and drop files too. You choose Mac OS Extended (Journaled).
  • A partition you want to take Time Machine backups too. Choose Mac OS Extended (Journaled).
  • For a partition you intend to use to share between a Mac and a Windows PC choose ExFAT for the format.

Next you set the size you want for the partition, using numbers and TB or GB.

5. To Create A Second Partition On Your Backup Plus

You click on the + sign to create your second partition.

Seagate Backup Plus Click Plus to Create 2nd Partition
Seagate Backup Plus Click Plus to Create 2nd Partition

You do the same things. Give the new partition a name, the format you want for it and a size.

Seagate Backup Plus Second Partition
Seagate Backup Plus Second Partition

Don’t worry if you get the sizing number a little wrong. Because your Mac will adjust the size of each partition slice to what is available.

Plus writing partitions uses up some of the space.

You’ll find the available space you’ve on the drive reduced a little.

If want you can go on to create more partitions exactly the same way.

And when you’re done.

6. Click Apply

Seagate Backup Plus Apply Partitioning
Seagate Backup Plus Apply Partitioning

Once you click apply your Mac will start to create each partition. It should only take a few minutes.

The partitions will show up quickly after that on your Mac’s desktop. You’ll see them as disk drive icons.

Each partition looking like a separate external hard drive on your desktop.

Drive and Partition Icons
Drive and Partition Icons

7. Close Disk Utility.

You can now close the Disk Utility window.

Click on the drive icons on the desktop to open them up and use.

And there you are. You’ve partitioned your Seagate Backup Plus for your Mac. You’ve shaped the external hard drive to exactly what you want on your Mac. And it’s ready for you to use it and love it on your Mac.

Partition Seagate Backup Plus Drive Frequently Asked Questions

1. Why Partition A Seagate Backup Plus?

You’ll find out there on the market the cost per TB of external storage getting cheaper and cheaper. You may well find it’s as cost effective for you to buy a larger external hard drive. Then split it up and use it for the tasks you want.

It may well be more efficient for you to use one external hard drive for your different files. Because you’d otherwise be buying two or three drives. So why not?

2. Will The Files On My Seagate Backup Plus Be Deleted If I Partition?

Yes, partitioning on a Mac is the same as formatting.

Yes, you’re separating one Seagate Backup Plus into different areas. But you format each area.

Partitioning will overwrite any files that are on the Seagate Backup Plus. So you should copy them off somewhere safe first if you plan to use them later.

3. Can I Partition Any Seagate Backup Plus External Hard Drive?


There are different types of Seagate Backup Plus drives sold under the Backup Plus name.

If you’ve a NTFS formatted drive it will need to be formatted to HFS+.

HFS+ is also known as Mac OS Extended (Journaled) file system.

And you’ll need to do this formatting before you partition your Backup Plus.

If you’ve got a Backup Plus Slim and it’s formatted as ExFAT then you’ll need to format it to HFS+ before partitioning it.

4. Partition Seagate Backup Plus For Time Machine

You can of course create a partition on your larger Seagate Backup Plus for a Time Machine Backup.

You should be sure the partition is large enough for your Time Machine Backup.

If you’ve 400GB of documents, music, photos, including your Mac’s operating system. Then you should have a partition 800GB in size. Plenty for you to backup to and to grow into over time.

You need to format a partition for Time Machine as HFS+.

Once you’ve created your partition for Time Machine you can easily add it to Time Machine.

Take a look at my article “Seagate Backup Plus Time Machine, the Smart Way to Backup” to find out how.

Adding your Time Machine partition to Time Machine for the software to backup up to is easy. You just add the partition name to Time Machine the same as you’d add the name of a whole disk drive.

5. Partition Seagate Backup Plus For Mac And PC

If your plan is to create a partition on your Seagate Backup Plus to share between your Mac and a Windows PC. Then you format the partition as ExFAT. 

In step 4 and 5 above I show you how you create your partitions. You select the ExFAT partition format instead of Mac OS Extended (Journaled).

A Mac and a PC can both read and write to an ExFAT partition. This means that when you plug in your Seagate Backup Plus into your Mac your Mac can see the Partition.

You can drag and drop your documents, photos, music. In fact whatever you like to the ExFAT partition. And then when you plug in your Backup Plus into a Windows PC the PC will see the partition.

And all your files on there.

Windows will not be able to see any Mac OS Extended (Journaled) formatted partitions. As a PC cannot see or read those.

What Are The Downsides To Partitioning A Seagate Backup Plus

It’s a very flexible way of using a larger Seagate Backup Plus.

But it means you’ve more on the drive.

Should something happen to your Backup Plus you’ll loose a lot of your files. Unless you keep a backup of that drive.

So make a copy onto a second drive. It’s the safest way to protect your files. And you can find out how in this article on the site. “Backup External Hard Drive to Another External Hard Drive on a Mac

I Try To Partition My Seagate Backup Plus And I Get An Error

The partitioning of your backup plus should go smoothly. But if you do get an error you should check and try these things.

1. Be sure you’re selecting the Backup Plus at the right level. Look again at Step 3 above.

2. Can your Mac see the drive at all? Is it on the desktop? If you can’t see it try plugging it into another port. Try rebooting your Mac. Can you see it on another computer such as a PC? If the answer to all these questions is no then you may have a bad drive.

3. If you get an error formatting or partitioning the drive. And you’re running Mac OS High Sierra it’s a common error with that operating system.

Just try it again and it often works.

4. If the drive formatted as NTFS and your trying to partition it? You’ll need to format it first as Mac OS Extended (Journaled) then partition.

Last Words

I hope you enjoyed my article “Partition Seagate Backup Plus Shape so You’ll Love it on Mac”. I have other documents on the site all about the Seagate Backup Plus. Do feel free to check them out.

How to Use Seagate Backup Plus on Mac, 15 Mins and Start

How to Format Seagate Backup Plus for Mac Help! Don’t Freak Out

Seagate Backup Plus Time Machine, the Smart Way to Backup

Seagate Backup Plus NTFS Driver for Mac Uncertain You Need It

Seagate Backup Plus Slim 2TB Review, Protect Your Family’s Docs

Seagate Expansion VS Backup Plus Who is on Top For Mac

Additional Resources

Seagate Backup Plus Manual – section on Partitioning