The shipping costs are calculated by the United States Post Office using the weight of the items ordered and the shipping address that the items are being sent to. The cost is shown during the checkout process. Most of the time, the USPS estimate of the shipping cost is a bit low. We honor the USPS estimate shown at check out even if we need to "chip in" to get that shipment to you. The research to find a sustainable and fair flat-rate option that we can implement for our Canadian customers is currently underway. Until we can find a better option, the current system charges actual cost for shipments under $200USD and Free Shipping for orders of $200USD and above. For now we have added a $10 discount on orders shipped to Canada that have a subtotal between $100USD and $200USD to help discount the shipping cost.