The 2020 presidential election is on November 3, but some states' voter registration deadlines are up to a month earlier.

Thirty-nine states allow their residents to easily register to vote online with proof of residency. In the others, you must register by mail or in-person.

Twenty states currently allow voters to register to vote on Election Day with valid proof of residency if they miss the deadline to register by mail or online.

If you're already registered to vote or have recently moved within your state, it's also a good time to update your registration if necessary or verify your registration to make sure it's still active.

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The 2020 presidential election is on November 3, but voter registration deadlines are coming up starting a month earlier in October.

The COVID-19 pandemic has caused rates of new voter registrations to dramatically decrease across the board as DMVs and other government service centers had to close down, and large gatherings and voter registration drives were prohibited by state-level stay-at-home orders.

Currently, 39 states allow their residents to easily register to vote online with proof of residency.

If you live in Arkansas, the District of Columbia, Maine, Mississippi, Montana, New Hampshire, Oklahoma, South Dakota, Texas, or Wyoming, you must register to vote either in-person at your local elections office or with a paper application mailed to your election office by your state's deadline.

And keep in mind that some states, you may not be able to use the online voter registration system if you don't have a driver's license or ID state ID card yet. If you're registering by mail, you'll want to make sure to get your paper application in well before the deadline, and not leave it up to chance.

North Dakota has no voter registration and instead requires voters to show ID at the polls in order to vote.

Twenty states currently allow voters to register to vote on Election Day if they miss the deadline to register by mail or online, according to the National Council of State Legislatures.

All the states that offer same-day registration require voters to present proof of residency with a valid photo or non-photo ID, with many states mandating those who do not have the requisite ID to cast a provisional ballot until their residency is verified.

While some allow voters to register directly at their polling places, others require same-day registrants to register at their county elections office, not a voting site, so be sure to double-check where to go in your county if you're registering on Election Day.

If you're already registered to vote or have recently moved within your state, it's also a good time to update your registration if necessary or verify your registration to make sure it's still active.

States perform routine voter list maintenance to remove people who have moved to another state, died, or become ineligible to vote due to a felony conviction from their voter rolls.

While such practices are an essential part of securing the integrity of elections, clerical errors and other mistakes mean that eligible voters can be taken off the rolls for not voting for a long period of time or, in more aggressive purges, mistakenly removed from the rolls for sharing the same name as a deceased, moved, or otherwise ineligible person.

Under the 2002 Help America Vote Act, states are prohibited from making any changes to their voter rolls within 90 days prior to a federal election, so you don't have to worry about being removed between now and November 3.

But it's still worth taking the time to double-check both your registration and your local polling location, which may have have been moved due to the pandemic.