As ranked choice voting (RCV) grows in popularity and use in US elections, it is important for policymakers, election administrators, and the general public to have a clear understanding of this voting method and its purpose. To provide clarity and precision for ranked choice voting methods, this document provides detailed technical specifications precisely defining all aspects of the ranked choice voting tabulation process.

This document is not designed as an introduction to RCV. It consists of technical guidelines intended to help policymakers and specialists understand, in depth, how RCV works and provide the technical details necessary to build accurate RCV counting tools. It provides technical specifications for RCV tabulation and discusses policy implications for the various counting rules currently used in ranked choice voting elections. Ranked choice voting, when used in this document, means the definition adopted by the National Institute of Standards and Technology (NIST):

• A set of election methods which allow each voter to rank contest options in order of the voter's preference, in which votes are counted in rounds using a series of runoff tabulations to defeat contest options with the fewest votes, and which elects a winner with a majority of final round votes in a single-winner contest and provides proportional representation in multi-winner contests.

This document also discusses other ranked ballot voting methods used in the United States. A number of jurisdictions have used or are considering the implementation of voting methods that ask voters to rank candidates. While these voting methods do use rankings, and the contests are marked in a preference or rank order, these non-RCV methods lack certain elements considered key to standard RCV as defined by NIST. These differences are revealed primarily in the tabulation processes applied to the voted ballots. This document details and demonstrates the tabulation processes associated with each of the ranked ballot voting methods that have been used or proposed for use in U.S. elections.

These other ranked ballot voting methods are described in order to contrast them with standard ranked choice voting methods. The differences are sometimes subtle but those differences have significant policy implications for those considering a new voting method.