How Pennsylvania Amends Its Constitution: A Simple Majority, Twice, With an Election in Between

If you ask someone what it takes to change Pennsylvania's constitution, many people will guess a two-thirds vote of the legislature, the Governor's signature, or both. Neither is required. Article XI, Section 1 requires a simple majority of the members elected to each chamber, and the Governor has no part in the process at all. It then goes as a referendum for Pennsylvanians to vote on.

The catch is that the majority has to hold twice, in two different legislatures, with an election in between. That second requirement is where many amendments fail, and it is where the party in control of each chamber holds the most power.

The process starts with first passage. The House and Senate each approve the proposed amendment, in identical wording, by a majority vote. Then comes an election. Pennsylvania's legislative sessions run two years, and the next session may seat a different majority.

In that next session, the amendment must pass both chambers again, in exactly the same words. If the wording changes, the process restarts at first passage. There is no governor signature step and no veto. Once second passage is secured, the proposal is advertised to the public and goes on the statewide ballot, where voters decide.

What makes the process hard is timing, not the size of the vote. The majority party in each chamber controls the calendar, meaning it decides what comes to the floor. If the party in control after the election does not want to advance an amendment, it can simply decline to schedule it. No procedure lets a minority party force the question, and when the session ends the amendment expires.

This often happens. Ballotpedia's review found that between 2010 and 2022, roughly half of the amendments that received first passage failed in the second session. When party control of a chamber changed between the two sessions, 79 percent failed, 11 of 14.

SB 106 is the clearest recent case. In July 2022, both chambers of the PA general assembly were under Republican control, and the amendment passed the Senate 28–22 and the House 107–92. The November election produced a 102–101 Democratic House, the amendment was never brought up again, and it expired on November 30, 2024 without a second vote in either chamber. "The One-Vote House" follows that case in full.

The brake is deliberate. The two-session rule exists so that a proposed amendment must survive a change of electorate before it reaches voters. It also makes each failed attempt costly. A proposal that stalls starts over at first passage, so the earliest realistic statewide vote on anything that begins in the next session is 2030.

A loss at the referendum stage sets the clock back further. Article XI bars the same amendment from going back to voters more than once in five years.

For a citizen following a proposed amendment, the first vote is the easy part to watch and the least telling. The question that decides its fate comes after the next election, when a new legislature decides whether to put it on the calendar at all.