Saturday 29 February 2020 (presumably): Precinct Caucuses. Republican Party Caucuses meet in each precinct to elect delegates to the County Convention or Legislative District Caucuses [WSRP rules 14, 15, 16]. The County Conventions will, in turn, choose delegates to the State Convention.

Voters must sign a political party declaration on the ballot return envelope and that declaration must match the voted candidate's political party. "I declare that I am a Republican and I have not participated and will not participate in the 2020 precinct caucus or convention system of any other party."

Tuesday 10 March 2020 (presumably): Washington Primary. Hours end at 8:00p PDT (0300 UTC). Washington votes by mail. Ballots must be postmarked on or before Election Day, or dropped off in a designated ballot box by 8 p.m. local time on Election Day. Delegate Selection: Combined Selection Statewide: Proportional, District: Winner-Take-Most Primary. Voter Eligibility: Closed Primary.

Primary
Source: Washington Secretary of State.
Status: Official. Retrieved: Thursday 26 March 2020.
Included in Nationwide vote.

All 43 of Washington's delegates to the Republican National Convention are allocated to presidential contenders based on the results of the voting in today's Presidential Primary.

• Each of the state's 10 congressional districts is allocated 3 delegates.
• If a candidate receives a majority of the vote or only 1 candidate receives 20% of the vote, that candidate receives all 3 delegates.
• If there are 2 candidates who receive at least 20% of the primary vote, then the top vote getter will be allocated 2 delegates and the other candidate will be allocated 1 delegate.
• If no candidate receives at least 20% of the vote or more than 2 candidates receive at least 20% of the vote, then the top three vote getters each receive 1 delegate.
• 13 at-large delegates (10 base at-large delegates plus 0 bonus delegates plus 3 RNC delegates) are allocated proportionally based on the statewide vote. At-Large candidates must receive at least 20% of the total statewide vote in order to be allocated delegates.
• Allocation is in proportion to the total statewide vote NOT the total vote of those candidates receiving 20% or more of statewide vote.
• Compute the number of delegates allocated to each Presidential candidate: 13 delegates × candidate's vote ÷ total statewide vote. Round to the nearest whole number.
• If more than 13 delegates are allocated, subtract 1 delegate from the candidate or candidates furthest from the rounding threshold until 13 delegates have been allocated.
• If fewer than 13 delegates are allocated (due to the 20% threshold or rounding), those delegates become unbound.

Primary
Source: Washington Secretary of State.
Status: Official. Retrieved: Thursday 26 March 2020.

CD1: 3 delegates for Trump, winner-take-all.
CD2: 3 delegates for Trump, winner-take-all.
CD3: 3 delegates for Trump, winner-take-all.
CD4: 3 delegates for Trump, winner-take-all.
CD5: 3 delegates for Trump, winner-take-all.
CD6: 3 delegates for Trump, winner-take-all.
CD7: 3 delegates for Trump, winner-take-all.
CD8: 3 delegates for Trump, winner-take-all.
CD9: 3 delegates for Trump, winner-take-all.
CD10: 3 delegates for Trump, winner-take-all.
Statewide is proportional for candidates 20%+ of the vote.
Trump: 13 delegates × 684,239 ÷ 695,275 = 12.794 rounds to 13 delegates. Difference: -0.206

Delegates are bound by the primary results only on the first ballot. If no candidate receives the majority ... on the first ballot, ... delegates will vote as they choose on successive ballots.

3 party leaders, the National Committeeman, the National Committeewoman, and the chairman of the Washington's Republican Party, will attend the convention as bound delegates by virtue of their position.

Saturday 14 March - Friday 17 April 2020 (presumably): Republican Party County Conventions and Legislative District Caucuses convene to elect delegates to the State Convention. [WSRP rule 19].

• 18 April: King County Convention.

Thursday 14 May - Saturday 16 May 2020 (presumably): The Washington Republican State Convention (consisting of 1,500 delegates, 1,500 alternates, and the automatic delegates) convenes [WSRP rule 36]. National Convention delegates are elected according to the results of the primary.