ITG FAQ #12 Answer-What if a contractor does not provide the tribe with a completed Form W-9?
The tribe should backup withhold. The earnings of the contractor are subject to backup withholding if no Form W-9, Request for Taxpayer Identification Number and Certification, is provided. The tribe should withhold at the current rate of 28%. Rates change from time to time. Be sure to check Publication 15, Circular E, Employer's Tax Guide, for the most current rates.