First-Time Homeowners Assistance Act of 2019 This bill establishes a tax-exempt qualified first-time homeowner assistance program. Under such a program, a person may make cash contributions to a first-time homeowner assistance account. The bill defines "first-time homeowner assistance account" as an account for providing down payment assistance to an account beneficiary who is a first-time homeowner of a principal residence in the United States. The amount of such downpayment assistance cannot exceed 10% of the cost of acquiring, constructing, or substantially improving the residence.