What do I do when I cannot get the social security number or address of subcontractors for their 1099 forms?

If the person fails to provide you with their social security number, you are required to backup withhold on the payments made to that person. The current backup withholding rate is 28%. You may also be subject to a penalty of up to $50 per information return that is filed without the necessary information. That penalty may be waived for reasonable cause, generally, if you requested the subcontractor's social security number and the contractor failed to provide it to you. You will have reasonable cause for not including the SSN on your 1099. In addition, the $50 penalty does not apply to any failure that does not hinder the IRS from processing the return, from correlating the information required to be shown on the return with the information shown on the payee's tax return, or from otherwise putting the return to its intended use.