BIN stands for Business Identification Number. It is a nine-digit number that identifies your business with the Ontario Ministry of Government Services. The service Ontario issues this number when you register your business with Service Ontario to obtain a Master Business License.
You need to obtain a master business license from Service Ontario:
The service Ontario charges you a fee for issuing the master business license. The license is valid for five years, expiring which you will need to renew it again.
The BIN should not be confused with the BN (business number). These two numbers are completely different. The BN (business number) is issued by the Canada Revenue Agency and you use this number when filing and paying taxes.