The old English term “boot” refers to “something that is given in addition to.” Boot in real estate is the non-like-kind property you receive in a 1031 exchange, which is generally in the form of cash or an installment note. However, boot can come in many forms, including mortgage reduction, where your replacement property has a smaller mortgage than your relinquished property, and non-transaction costs, where you use sales proceeds from your exchange to pay certain expenses.