Can I use this one app for more than one business?

Hello, @mosdephdesigns.

At this time, QuickBooks Online (QBO) can only handle one company file per subscription. If you have multiple companies, you 'll need to sign up for a new QBO account. This means each company has its subscription. But the good thing is, you can use the same login credentials for all your companies so that the accounts are listed in one place when you log in. 

To learn more about creating new companies or switching from one company to the other, check out these articles:

• Create or add another company
• How do I switch companies?

As always, skim through our help articles in case you need related links while working with QuickBooks in the future.

Please know that I'm only a post away if you have any other issues or concerns. Just add a comment below. Have a good one!

@mosdephdesigns 

If you have to open a new QBO account, make sure to click the Buy button to get the discounted price for up to 6 months. If you purchase from the trial account, you have to pay the regular price.

https:// quickbooks.grsm.io/US

https:// quickbooks.grsm.io/us-promo

Otherwise, consider switching to QB Desktop to craete and manage multi company files without extra cost.