Download macOS Sequoia for second volume without upgrading main OS on MacBook Pro

Question

Level 1

9 points

Download macOS Sequoia for second volume without upgrading main OS on MacBook Pro

I have a 2019 MacBook Pro 16".

The main Volume runs Mojave OS. I have added a second volume so I can add OS Sequoia as a second, separate bootable drive (selected by pressing OPTION key when starting the Mac)..

My problem is this: when I go to the App Store to download Sequoia, it opens Software Update, which asks me if I want to download and upgrade my OS. I do NOT want to upgrade, I just want to download Sequoia and be given the option of which drive I wish the new OS to be installed.

I have tried using disc utility in Recovery Mode as well, but it only offers the option to reinstall Mojave.

Your help in resolving this is most appreciated

MacBook Pro 15″, macOS 10.14

Posted on Sep 10, 2026 8:41 AM

Reply

Answer 1

Sep 10, 2026 10:57 AM in response to lovely272

Here is an Apple article with links & instructions to download various macOS installers:

How to download and install macOS - Apple Support

Just want to check that you just made a new APFS volume for the Sequoia installation:

Add, delete, or erase APFS volumes in Disk Utility on Mac - Apple Support

Reply

Answer 2

MartinR

Level 7

26,544 points

Sep 10, 2026 1:56 PM in response to lovely272

Something doesn't sound right here. The 16" 2019 MBPros came with Catalina preinstalled (10.15.1).

The 13" & 15" MBPro models in 2019 came with Mojave 10.14.5.

Regardless, I wouldn't jump all the way from Mojave to Sequoia in one step. There were major changes along the way, especially in Catalina & Monterey. I suggest upgrading to Catalina first, then if all is ok upgrade from there to Sequoia. Note that no 32-bit apps are going to work on anything past Mojave.

Mr Macintosh has details about how to download most versions of macOS including Mojave and later. Read the page thoroughly before trying any of the download methods.

Make sure the target drive/volume is formatted as APFS.

And make sure you have a good backup on an external drive before doing any of this. Two backups is even better.

Reply

Answer 3

lovely272 Author

Level 1

9 points

Sep 10, 2026 2:32 PM in response to MartinR

If you read my post, I am not trying to jump from one OS to another. I have set up a separate Volume in order to install Sequoia onto it, thereby leaving my main Volume with Mojave unaffected.

Reply

Answer 4

lovely272 Author

Level 1

9 points

Sep 10, 2026 2:34 PM in response to HWTech

Yes, I followed these directions but they all lead to asking to UPGRADE to Sequoia. I don't want an upgrade, I want a standalone OS on anew ASPS volume I have created for this new OS

Reply