You will only have a client ID number if you are the sponsorer and you have already sent in your application and have been notified by CIC Missisuga what your client ID # is. This ID # is on the letter CIC Missisuga sends when they have approved / denied your application to sponsor.
If you have not applied already and you are sending in the receipt with applicaiton you can leave the section blank.
If you have already applied check on the letter you received from Missisauga (same number you use to check ecas)
KC