(1) Except as provided in RCW 41.26.530, a member of the retirement system shall receive a retirement allowance equal to two percent of such member's final average salary for each year of service.
(2) Beginning January 16, 2023, members new to the retirement system after February 1, 2021, who earn more than 15 years of service credit shall receive a tiered multiplier retirement allowance as follows:
(a) Two percent of such member's final average salary for the first 15 years of service;
(b) Two and one-half percent of such member's final average salary for the 10 years of service after 15 years and up to 25 years; and
(c) Two percent of such member's final average salary for years of service above 25 years.
(3) Members active in the retirement system on or before February 1, 2021, at retirement must make an irrevocable choice between the lump sum defined benefit in RCW 41.26.555 or a tiered multiplier retirement allowance as follows:
(a) Two percent of such member's final average salary for the first 15 years of service;
(b) Two and one-half percent of such member's final average salary for the 10 years of service after 15 years and up to 25 years; and
(c) Two percent of such member's final average salary for years of service above 25 years.
(4) Any member who receives the tiered multiplier benefit in this section is not eligible for the lump sum defined benefit in RCW 41.26.555.