Resale Number Vs. Tax ID. Running your own business requires the correct documentation. Don’t be fooled into thinking that because you’ve gotten one license, you’re set. Different tax numbers serve different purposes.
Each time you begin a new job, one of the forms you’ll be asked to fill out is a Form W-4. This form helps your employer determine how much to withhold from your paycheck in taxes, based on the number of exemptions you claim on your tax return.