I am trying to enter a new vendor's information under payroll. When I try to enter the EIN, it says its in the wrong format. It will allow me to enter it as a SSN

Hello there, @invoices-ses. 

I'd be glad to provide details about how EIN and SSN works in QuickBooks Online (QBO).

Enter an EIN using this format: XX-XXXXXXX. For SSN, go with this format: XXX-XX-XXXX.

On top of that, if you still want to use the EIN in your vendor's information. Then, you can tick the box next to Track payments for 1099 to use it.

To learn more about preparing your Federal 1099s, consider checking out this article: File 099s using QuickBooks Online.

I've also included an article about creating a 1099 report for vendors and vendor payments. This allows you to view what you've paid to your vendors.

If you have any concerns while working in QBO, leave me a comment. I’ll be happy to lend a helping hand. Have a wonderful day!