Officially the MS policy is that you can't.
Fortunately, there is an unofficial work around you can try:
Roll Back 2016 to 2013 manually by USER! DownGrade - Down Grade - Back out
How do I reinstall Office 2013 after an Office 2016 upgrade?
https://support.office.com/en-US/article/How-do-I-reinstall-Office-2013-after-an-Office-2016-upgrade-a6ca92f4-cbb4-4609-9fdb-f8d3dd6812f3
Alternate Down Grade method - Use 365 Deployment Tool
http://answers.microsoft.com/en-us/office/forum/office_2016-outlook/rolling-back-to-2013-from-2016/edda2c54-de95-446f-a306-59c688f15899?page=3&msgId=1f48defc-0069-4609-bb7d-1d4ca68481e9
<snip>
I had the same issue, I kept getting the answer that it was IMPOSSIBLE from multiple Answer Desk associates!
After almost giving up, I found a way to download and install the software manually using their own Deployment Tool. Another good thing about using this tool is that I can keep a copy of the program offline in case I run into issues down the road and want
to reinstall Office 2013.
The tool to use is the Office 365 Deployment Tool for Click to Run, normally used for administrators to use for installations across multiple PCs.
The download for the executable is at:
https://www.microsoft.com/en-ca/download/details.aspx?id=36778
After downloading the tool, you just need to edit a couple of configuration files. One to download the Office archive and one to install the archive.
I found some tips on how to use it at: https://blog.vsean.net/post/
example for Office 365 Home I used.
- <Configuration>
- <Add SourcePath=”C:\Office15\” OfficeClientEdition=”32” >
- <Product ID=”O365HomePremRetail”>
- <Language ID=”en-us” />
- </Product>
- </Add>
- </Configuration>
- <Configuration>
- <Add SourcePath=”C:\Office15\” Version=”15.0.4753.1003” OfficeClientEdition=”32” >
- <Product ID=”O365HomePremRetail”>
- <Language ID=”en-us” />
- </Product>
- </Add>
- <Display Level=”Full” AcceptEULA=”TRUE” />
- </Configuration> The other Product ID codes are located at:
https://blog.vsean.net/post/191
Big thanks to that website.
Hope that helps. Crazy how many issues I had with my Surface Pro 3 and Windows 10 and Office 2016, but it runs like a champ on my desktops!
-Dry
</snip>
Get Help from MS Support to Roll Back - ‘We need to remove some older apps” error’
http://answers.microsoft.com/en-us/office/forum/office_2016-outlook/rolling-back-to-2013-from-2016/edda2c54-de95-446f-a306-59c688f158f99?page=3&msgId=1f48defc-0069-4609-bb7d-1d4ca68481e9
https://community.office365.com/en-us/f/172/t/409681
We have a solution within Support for that. The issue is documented here: https://support.office.com/article/-We-need-to-remove-some-older-apps-error-a225347f-e102-4ea6-9796-5d1ac5220c3b
When you contact Support, let them know you are upgrading your Office 2013 subscription to 2016 and are getting a message that Visio or Project needs to be removed. The support agents are being reminded of this situation and how to resolve it.
</snip>
People who have home/personal can also work through support on getting this resolved, and they have a process to get you back on 2013. If the support person is not providing you with a method to re-install 2013, feel free to give them my name as I am on
the product engineering team, and own the compatibility matrix and the process for what to do for customers that currently connect to Exchange 2007
Let me know if you are unable to get this resolved.
Erik Ashby
Principal Program Manger
Outlook Org
</snip>
2013 Home Prem CTR Download Link
https://c2rsetup.officeapps.live.com/c2r/download.aspx?productReleaseID=O365HomePremRetail&platform=X86&language=en-US&TaxRegion=pr&correlationId=2491f612-e060-4d3c-beef-bc8149bb07fd&token=fd38e9c7-123e-4816-bb2b-d214abf849e2&version=O15GA&source=O15OLSOMEX