You are required to solicit the taxpayer identification of anyone for whom you are required to file a 1099-NEC form--this is normally done on Form W-9. If the

You are required to solicit the taxpayer identification of anyone for whom you are required to file a 1099-NEC form--this is normally done on Form W-9. If the contractor fails to furnish a TIN, you are not required to cease business with them, however you will likely have to respond to the IRS and show that they refused to tell you when you file the 1099s each year. The IRS can assess a $50 civil penalty against the contractor (doubt they bother due to low amount set in statute), but more importantly the employer must withhold 30% backup withholding due to the failure to provide TIN. The employer will have to report the income and withholding on their tax return, which will likely be held up while the IRS verifies the match. I-9/E-Verify is for employees of your entity only and is not completed for independent contractors, nor for temp/contract labor who is employed by a different company (they do the form).