Example. The tax return due date is Friday, December 25th, a legal and banking holiday. The next business day is Monday, December 28th, and this is the holiday-adjusted tax return due date. This means EFT debit and e-check users must initiate their debit payment by 11:59 p.m., Pacific Time, on December 28th, with a payment effective date of Tuesday, December 29th, for the payment to be considered timely. EFT credit users must contact their bank to ensure funds are deposited in the department's bank no later than 5:00 p.m., Pacific Time, on Tuesday, December 29th, for the payment to be considered timely.
Wash. Admin. Code § 458-20-22802