Direct answer: In the United States, you typically don’t need to re-register before every election. You generally only need to register once, and you update or re-register if you move, change your name, or otherwise need to update your registration details. The exact deadlines and rules vary by state, so check your state or local election office for the current deadline to register or update registration ahead of an election. Details by common scenarios:

• If you’ve moved within your state: update your registration with your new address.
• If you’ve moved to a new state: you must register in your new state.
• If you’ve changed your name: you’ll need to update your registration to reflect the new name.
• If your party affiliation or other registration details need updating: many states allow updating online or by submitting a new registration.

For UK or other countries, the registration rules differ (e.g., in the UK you register to vote at your current address, and you don’t re-register for each election unless your details change). If you’d like, provide your country or state, and I’ll give you the exact current deadline and steps for that jurisdiction.