We want to continue offering free shipping on domestic packages. However, because of the high cost of shipping even a small package, we cannot afford to ship single samples where the price does not cover the cost of USPS postage, let alone the cost of the sample itself. For that reason, there is a minimum purchase amount of $6.00, which is equivalent to two samples. That covers the shipping charge, and the samples are almost free. For international sample orders, the minimum purchase amount is $30.00 to cover the cost of shipping and handling.