Use Form W-9 to get his SSN. A copy is here: <a rel="nofollow" target="_blank" href="
https://www.irs.gov/pub/irs-pdf/fw9.pdf">https://www.irs.gov/pub/irs-pdf/fw9.pdf</a> . It's much easier to get the W-9 completed BEFORE you give him the check instead of after..
