upgrade from sierra to monterey

The MacBook Pro (Retina, 13-inch, early-2015) can be upgraded to MacOS 12 Monterey.

➡️ macOS 11 Big Sur is compatible with the Macs listed here

➡️ macOS 12 Monterey is compatible with the Macs listed here

The upgrade is not difficult. And as you posted, yes, you do need to backup the Mac before attempting this, just in case. I believe you can upgrade directly from Sierra to Monterey, but the links to the intermediate macOS upgrades are also below.

❗️ – IMPORTANT – None of your 32-bit apps will work in macOS Catalina or newer. This includes older MS Office apps and any other older software apps and drivers. These will require that you find 64-bit updates and/or replacement titles. 32-bit app compatibility with macOS High Sierra 10.13.4 and later - Apple Support

Use the free utility Go64 to check the 64-bit compatibility of your apps:

https://www.stclairsoft.com/Go64/

✅ - Download the appropriate macOS upgrade installer app:

Click > 10.13 High Sierra,  10.14 Mojave,  10.15 Catalina or  macOS 11 Big Sur or macOS 12 Monterey.

Once downloaded, double-click the “Install macOS…” app in the Applications folder to begin the upgrade.

Please see > How to download macOS - Apple Support.

alistair173 wrote:

How easy is to upgrade from a MacBook 13 inch retina early 2015 using Sierra to Monterey? I am aware that I need to back up using time machine but need advice from there.

I have a 2015 iMac, and upgraded it from Sierra to Monterey last year. In principle, you can do it in one step. However I did it step-wise, one MacOS at a time. It worked well. It took an hour or two, if you have a fast internet connection the updates/upgrades download and install quickly. There were no issues.

These older MacOS version are available here: How to download and install macOS - Apple Support

I would suggest at least two backups before doing this, and they should be different types, for instance one should be Time Machine and the other could be a "clone" type backup such as CCC or SuperDuper.

At some point in this process your internal drive will be changed from HFS+ to APFS. This is not an issue but something to be aware of. APFS works well with SSDs, but is slow with mechanical hard drives. I believe yours has an internal SSD so it should be no problem.

Also, older 32-bit software will stop working after Mojave. You might review your currently installed software to see if any old versions will need to be replaced. That could include some Microsoft and Adobe applications, among others.

P.S. (note added) I see that D.I. Johnson posted while I was writing the above, some of what I posted is redundant with his advice.

10.13 High Sierra makes the initial change to APFS if you have an SSD boot drive.

Catalina sets aside all older 32-bits only Apps.