No, it is not necessary to provide a completed exemption certificate and a copy of Form R-1091, Commercial Farmer Certification, each time a purchase is made from the same vendor. The selling vendor is required to retain the properly executed exemption certificate with a copy of a valid Commercial Farmer Certification on file, therefore, each vendor you use will need their own copies. The selling vendor can apply a current exemption certificate on file to future qualifying farm related purchases up to the expiration date of the Commercial Farmer Certification. New documentation will be required upon renewal.

For example, a commercial farmer has a certification that expires July 31, 2022. The commercial farmer provides the selling vendor with an executed exemption certificate (R-1007, R-1060, R-1065, or R-80001 as applicable) and a copy of the R-1091 Commercial Farmer Certification, on August 25, 2019. The executed certification will be valid until July 31, 2022, when Form R-1091 Commercial Farmer Certification, expires.