This bill introduces a new provision to chapter 82.87 RCW, allowing taxpayers to prepay their capital gains taxes up to six months before the due date for filing and payment. Taxpayers can submit these payments in the manner and form prescribed by the department, providing them with greater flexibility in managing their tax obligations.

Additionally, the bill stipulates that if the department determines a taxpayer has overpaid their taxes for the taxable year, no interest will be assessed for the period prior to the due date. This provision aims to alleviate potential financial burdens on taxpayers who may inadvertently overpay their taxes.