What Happens if a Vacancy Happens in Either Chamber in Congress?

States have some flexibility if they have to fill a vacancy in the Senate. The U.S. Constitution sets some limitations, but, within those rules, each state determines its own method. States must hold elections, but, until the ballots are counted, all but four states let their governor select an interim senator. The seat must remain empty until the election in those states. In Hawaii, Utah and Wyoming, the governor’s choice must be a member of the same political party as the former senator. In addition, Hawaii’s governor must choose an appointee from a list of three candidates that the party recommends.

The timing of the election is up to the states. In 36 states a replacement senator is elected at the next regularly scheduled election. If the previous senator’s term was up, the new senator serves a full 6-year term. Otherwise, the replacement fills out the remaining years of the term. Fourteen states hold a special senatorial election. Most states require the special election to be held two to four months after the vacancy occurs. However, if the opening happens relatively close to the general election, states often skip the special voting day.

For vacancies in the House of Representatives, all states must follow certain procedures. Congress is divided into two sessions, each lasting a year. If a House opening occurs during the first Congressional session, the state must hold a special election to fill the seat. If the vacancy appears during the second session, it’s up to the state to determine if there is a special election, or if the state will wait until the general election. This decision is usually based upon the length of time from the date of the opening until the scheduled election. If it’s a relatively short time, a special election is usually not held.

It can take months to fill a seat in the House of Representatives. Therefore, some people recommend that the law be changed, making it similar to filling Senate vacancies, where a governor often makes an interim appointment. As of now, there is no representative in a vacant seat until an election. In the case of a catastrophe such as a terrorist attack, it’s possible that a large number of representatives could be killed or so badly injured they could no longer serve. Severely reduced numbers in the House could make it extremely difficult for it to function. If governors could appoint interim replacements, the House could be in working order much more quickly.