The bill modifies the working families' tax credit in Washington State by clarifying its refundable nature, application requirements, and eligibility verification process. It reenacts and amends RCW 82.08.0206, establishing that the credit is funded by sales and use tax imposed on eligible low-income individuals starting from calendar years beginning on or after January 1, 2022. The bill specifies that eligible individuals must be Washington residents, have filed a federal income tax return, and have paid retail sales or use tax. It also introduces a rebuttable presumption that individuals who were Washington residents during the year for which the credit is claimed have paid the necessary taxes.

Additionally, the bill outlines the refund amounts based on the number of qualifying children and sets forth a process for application and verification of eligibility. It includes provisions for adjusting refund amounts for inflation and allows individuals to apply for refunds for up to three years after the tax year in question. The department is tasked with protecting the privacy of applicants and may use automated verification tools to confirm residency and eligibility. The act applies both prospectively and retroactively to January 1, 2023.