Source: https://www.brennancenter.org/analysis/movers-guide-montana
Timestamp: 2019-04-25 12:45:19+00:00

Document:
If you moved to Montana from another state, you must register to vote in Montana to be able to vote. You can register in person at the election administrator’s office anytime before the election; however, any voter who registers after noon on the day before or on Election Day must appear at the county election office in order to vote. Unless you register at the election administrator’s office, the last day to register in time to vote in the next election is thirty days before the election.
If you moved from out of state, you are only eligible to register if you have been a resident of Montana and of the county in which you want to vote for at least thirty days. But under federal law, if you move within thirty days of a presidential election, you are allowed to vote for President and Vice President in your former state of residence, either in person or by absentee ballot.
Montana voters who move are still entitled to cast a ballot that will be counted — even if they did not notify the appropriate election official about the move before Election Day.
If you moved to a new address within the same county but with a different polling place, you can vote at the polling place associated with your old address or a centralized location set up by the election administrator for the first election after your move. You need to give your new address and fill out a transfer or new registration form.
Alternately, you can update your registration and vote in person at your county election administrator’s office on Election Day.
If you moved to a new address in a different county more than 30 days before an election you should complete a new registration form for your new address in the county.
Update your registration and vote in your new polling place.
Register to vote or update your registration and vote in person at your county election administrator’s office on Election Day.
 Mont. Code Ann. § 13-1-111(1)(a) (2010).
 Mont. Code Ann. § 13-2-304; Mont. Admin. R. 44.3.2015 (2010).
 Mont. Code Ann. §§ 13-2-301(1)(a), -304.
 Mont. Code Ann. § 13-1-111(1)(c).
 Mont. Code Ann. § 13-2-511 (2010).
 Mont. Code Ann. § 13-2-514.
 Mont. Code Ann. § 13-2-512(3).
 Mont. Code Ann. § 13-2-512(1).
 Mont. Code Ann. § 13-2-512 (3).
 Mont. Code Ann. § 13-2-514(1).
 Mont. Code Ann. § 13-2-514(2)(a).
 Mont. Code Ann. § 13-2-514(2)(b).
 Mont. Code Ann. § 13-2-304; Mont. Admin. R. 44.3.2015.

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