What if vendor refuses to give us federal ID number for 1099 misc forms?

If a vendor refuses to provide their federal ID number for 1099-MISC forms, you should document your attempts to obtain the information and inform the vendor of their legal obligation to provide it. You can also remind them that failing to provide this information may result in backup withholding. If they still refuse, you should consult with your tax advisor or legal counsel for guidance on how to proceed and ensure compliance with IRS regulations.