When you buy an existing business, it usually involves paying out significant amounts of money, and cash flow planning is crucial. Under the rules of the goods and services tax and harmonized sales tax, the sale of a business is a taxable supply, so you technically need to pay the tax to the seller. If you are registered for the GST/HST, you will eventually recover it as an input tax credit, but that process can take weeks or even months, leaving you with a cash flow issue.There is a legal way to avoid paying the tax. The Excise Tax Act, where the GST/HST provisions are found, provides relief of the payment of the tax if the buyer and the seller jointly agree to waive it and certain other criteria are met. As a rule, you can make this election if the seller is supplying a business or part of it that was carried on actively and you acquire substantially all of the assets required to continue to carry on the business.First, as a buyer, you need to be registered for the GST/HST. If you are using a new company to make the acquisition, make sure it is registered before you proceed. Second, you need to complete Form GST44 and file it with the Canada Revenue Agency with your next GST/HST return. This little-known election is very useful and can help alleviate cash flow issues as well as saving you a lot of money on financing costs when you’re buying a business.