Which Tax ID to use on the Vendor

Question

I need some assistance on what is the generally accepted practice on tax id's.
On the Control screen, there is tax id1 and tax id2.  THen on the Company Code Withholding screen, there is the 1099 information and tax id.
If I have a vendor that is 1099 applicable, should the tax id get entered on the Control Screen and the Withholding screen
or
If I enter the tax id on the Control Screen, and fill in the 1099 information on the Withholding screen (except for the tax id), will the system automatically use the tax id on the Control screen for 1099 processing?
or
If the vendor is 1099 applicable, nothing is entered on the Control screen and the 1099 data including tax id is entered on the Withholding screen.
Thank you
Cindy

Answer 1

That doesn't really answer my question.  You are saying putting it in one or the other.  It doesn't say when you would use one or the other or both.
As a company we require a w-9 from our vendors, the tax id on the w-9 is either a SSAN or Fed ID #.  Some of these vendors are 1099 applicable.  We want to enter the tax id # whether they are 1099 applicable or not. 
For 1099 reporting, we report paid amounts only.  We do not collect tax for any amounts paid to vendors.
With this information, where would I put the tax id if:
Not 1099 applicable, federal tax id
Not 1099 applicable, ssan
1099 applicable, federal tax id
1099 applicable, ssan
THank you
Cindy