The list of Oregon ballot measures lists all statewide ballot measures to the present.

In Oregon, the initiative and referendum process dates back to 1902, when the efforts of the Direct Legislation League prompted amending the Oregon Constitution for the first time since 1859. The process of initiative and referendum became nationally known as the Oregon System.^[1][2]

There are three types of ballot measures: initiatives, referendums, and referrals. Initiatives and referendums may be placed on the ballot if their supporters gather enough signatures from Oregon voters; the number of signatures is a percentage based on the number of voters casting ballots in the most recent election for the Governor of Oregon.

Initiative

Any issue may be placed before the voters, either amending the Constitution or revising or adding to the Oregon Revised Statutes. Constitutional initiatives require the signature of eight percent of recent voters to qualify for the ballot; statutory reforms require six percent.

Referendum

The public may act to undo any bill passed by the Oregon Legislative Assembly, by putting a referendum on the ballot. A referendum requires four percent of recent voters to qualify for the ballot.

Legislative referral

The Legislative Assembly may refer any bill it passes to the public for approval, and they must do so for any amendment to the Constitution. Additionally, the Legislative Assembly may refer revisions to the Constitution; a revision differs from an amendment in that it may alter multiple existing provisions of the Constitution.

The constitutional foundation for ballot measures (and legislation produced by the Oregon Legislative Assembly) may be found in Article IV of the Oregon Constitution,^[3] and Chapter 250 of the Oregon Revised Statutes^[4] relates to initiative and referendum as well.

The Oregon Blue Book, produced by the Oregon government, maintains a list similar to this one.^[5]