Tax Filing Simplification Act of 201 9 This bill requires the Internal Revenue Service (IRS) to establish and operate the following programs free of charge online tax preparation and filing software, a program for taxpayers to download third-party provided return information relating to individual income tax returns, a program to permit individuals with simplified tax situations to elect to have the IRS prepare their returns, and a program to provide technical assistance and disclose federal income tax return information to states that provide or seek to provide state-level tax filing and preparation software. The IRS may not enter into any agreement that restricts its legal right to provide tax return preparation services, software, or tax return filing services. Individuals participating in, or accessing information from, the programs established by this bill must verify their identity to the satisfaction of the IRS. The IRS may not employ knowledge-based verification procedures to verify the identity of the individuals.