Effective January 1, 2018, a 15 percent cannabis excise tax applies to the average market price of the retail sale of cannabis products. Retailers engaged in business in California must also pay the state's sales tax of 7.25 percent and in some cases a local jurisdiction district tax which ranges from 0.10 to 1.00 percent. Some areas may have more than one district tax in effect. The entire sales tax applies to all retail sales of goods and merchandise except those sales specifically exempted by law. The sales tax due on your taxable cannabis sales at retail must be computed on your selling price of cannabis, plus the cannabis excise tax.