Mass contact upload without notifying

Morning community buddies,

I am looking to upload all of my companys' contacts into Smartsheet for two reasons:

1) So anyone in the business can appear in a contact drop-down - as some may not use Smartsheet but we in the PMO would be able to track resources - free text could lead to mistakes so it needs to be the same contact across anyone in the businesses sheets

2) So that when they do come to using Smartsheet they are already set-up

The issue I have is I believe when setting someone up as a User they receive an email notification advising of this. I want to stop this as some will never need to and will never use Smartsheet, so I wish to avoid the hundreds of 'What is this and why have you signed me up to it' emails that will follow.

Any ideas / advice on how to suppress these notifications?

Thanks,

Jack