Pennsylvania voters can download and mail in the Voter Registration Form. 
This is a PDF file and requires Adobe Acrobat Reader to view. 

Voter Registration

Voter registration is established by law throughout Pennsylvania. All electors, except members of the Armed Forces and bedridden or hospitalized veterans unavoidably absent from the country of residence, must be registered to be eligible to vote. After registration, unless he or she changes his or her residence, an elector is not required to register again. 

Qualifications of Voters

Individuals possessing the following qualifications are entitled to register to vote:

* must be 18 years on the day of the next election. They must have been citizens of the United States for at least one month.

* must have resided in the state for 30 days immediately preceding the election. They must have resided in the election district where they vote at least 30 days prior to the election (a voter who moves within the 30 days may vote in the district from which they moved).

Can Felons Vote?

The Commonwealth Court of Pennsylvania ruled on December 26, 2000 that the Pennsylvania law prohibiting convicted felons from registering to vote for five years after their release from prison is unconstitutional. Consequently, if completing an older version of the Voter Registration Mail Application (VRMA) form, a convicted felon who has been released from prison may make application to register to vote by striking through the felony conviction line at Section 9(2) on the VRMA and signing his or her name.

Convicted felons who are incarcerated on the date of a primary or general election are not eligible to vote, regardless of whether they are registered. However, pre-trial detainees and misdemeanants are eligible to register to vote and/or to vote by absentee ballot if they otherwise qualify to vote under law.
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Deadline to Register to Vote

Register in person at the Lycoming County Voter Registration Office in the courthouse annex on Pine Street in Williamsport.

Register to vote in conjunction with an application for, or renewal of, a Driver's License.

Register to Vote by Mail. A registration mail application is available to all persons and organizations upon request. This includes candidates, political parties, and political bodies.
Must be received — 30 days before an election or primary.