| State | Voter registration deadline (online) | Voter registration deadline (by-mail). | Voter registration deadline (in-person) | Register to vote |
|---|---|---|---|---|
| Alabama | 15 days before Election Day | Postmarked 15 days before Election Day | 15 days before Election Day | Register to vote in Alabama |
| Alaska | 30 days before Election Day | Postmarked 30 days before Election Day | 30 days before Election Day | Register to vote in Alaska |
| Arizona | 29 days before Election Day | Postmarked 29 days before Election Day | 29 days before Election Day | Register to vote in Arizona |
| Arkansas | N/A | Postmarked 30 days before Election Day | 30 days before Election Day | Register to vote in Arkansas |
| California | 15 days before Election Day | Postmarked 15 days before Election Day | Election Day | Register to vote in California |
| Colorado | 8 days before Election Day | Received 8 days before Election Day | Election Day | Register to vote in Colorado |
| Connecticut | 7 days before Election Day | Postmarked 7 days before Election Day | Election Day | Register to vote in Connecticut |
| Delaware | 24 days before Election Day | Postmarked 24 days before Election Day | 24 days before Election Day | Register to vote in Delaware |
| District of Columbia | 21 days before Election Day | Received 21 days before Election Day | Election Day | Register to vote in District of Columbia |
| Florida | 29 days before Election Day | Postmarked 29 days before Election Day | 29 days before Election Day | Register to vote in Florida |
| Georgia | 29 days before Election Day | Postmarked 29 days before Election Day | 29 days before Election Day | Register to vote in Georgia |
| Hawaii | 29 days before Election Day | Received 29 days before Election Day | 3 days before Election Day | Register to vote in Hawaii |
| Idaho | 25 days before Election Day | Postmarked 25 days before Election Day | Election Day | Register to vote in Idaho |
| Illinois | 16 days before Election Day | Postmarked 28 days before Election Day | Election Day | Register to vote in Illinois |
| Indiana | 29 days before Election Day | Postmarked 29 days before Election Day | 29 days before Election Day | Register to vote in Indiana |
| Iowa | 10 days before Election Day | Postmarked 15 days before Election Day | 10 days before Election Day | Register to vote in Iowa |
| Kansas | 21 days before Election Day | Postmarked 21 days before Election Day | 21 days before Election Day | Register to vote in Kansas |
| Kentucky | 29 days before Election Day | Postmarked 29 days before Election Day | 29 days before Election Day | Register to vote in Kentucky |
| Louisiana | 20 days before Election Day | Received 30 days before Election Day | 30 days before Election Day | Register to vote in Louisiana |
| Maine | N/A | Received 21 business days before Election Day | Election Day | Register to vote in Maine |
| Maryland | 21 days before Election Day | Postmarked 21 days before Election Day | Election Day | Register to vote in Maryland |
| Massachusetts | 20 days before Election Day | Postmarked 20 days before Election Day | Election Day | Register to vote in Massachusetts |
| Michigan | 14 days before Election Day | Postmarked 14 days before Election Day | Election Day | Register to vote in Michigan |
| Minnesota | 21 days before Election Day | Received 21 days before Election Day | Election Day | Register to vote in Minnesota |
| Mississippi | N/A | Postmarked 30 days before Election Day | 30 days before Election Day | Register to vote in Mississippi |
| Missouri | 27 days before Election Day | Postmarked 27 days before Election Day | 27 days before Election Day | Register to vote in Missouri |
| Montana | N/A | Postmarked 30 days before Election Day | Election Day | Register to vote in Montana |
| Nebraska | 18 days before Election Day | Postmarked 18 days before Election Day | 11 days before Election Day | Register to vote in Nebraska |
| Nevada | 5 days before Election Day | Postmarked 28 days before Election Day | 28 days before Election Day | Register to vote in Nevada |
| New Hampshire | N/A | Received 14 days before Election Day | Election Day | Register to vote in New Hampshire |
| New Jersey | N/A | Received 21 days before Election Day | 21 days before Election Day | Register to vote in New Jersey |
| New Mexico | 28 days before Election Day | 28 days before Election Day | 28 days before Election Day | Register to vote in New Mexico |
| New York | 25 days before Election Day | Postmarked 25 days before Election Day | 25 days before Election Day | Register to vote in New York |
| North Carolina | 25 days before Election Day | Postmarked 25 days before Election Day | 3 days before Election Day | Register to vote in North Carolina |
| North Dakota | N/A | N/A | N/A | Register to vote in North Dakota |
| Ohio | 30 days before Election Day | 30 days before Election Day | 30 days before Election Day | Register to vote in Ohio |
| Oklahoma | N/A | Postmarked 25 days before Election Day | 25 days before Election Day | Register to vote in Oklahoma |
| Oregon | 21 days before Election Day | Received 21 days before Election Day | 21 days before Election Day | Register to vote in Oregon |
| Pennsylvania | 15 days prior to an election | Postmarked 15 days prior to an election | 15 days prior to an election | Register to vote in Pennsylvania |
| Rhode Island | 30 days before Election Day | Received 30 days before Election Day | Election Day for presidential elections, otherwise 30 days before Election Day | Register to vote in Rhode Island |
| South Carolina | 30 days before Election Day | 30 days before Election Day | 30 days before Election Day | Register to vote in South Carolina |
| South Dakota | N/A | Received 15 days before Election Day | 15 days before Election Day | Register to vote in South Dakota |
| Tennessee | 30 days before Election Day | Postmarked 30 days before Election Day | 30 days before Election Day | Register to vote in Tennessee |
| Texas | N/A | Postmarked 30 days before Election Day | 30 days before Election Day | Register to vote in Texas |
| Utah | 7 days before Election Day | Postmarked 30 days before Election Day | 7 days before Election Day | Register to vote in Utah |
| Vermont | 1 day before Election Day | Received 6 days before Election Day | Election Day | Register to vote in Vermont |
| Virginia | 22 days before Election Day | Postmarked 22 days before election | 22 days before Day | Register to vote in Virginia |
| Washington | 8 days before Election Day | Received 8 days before Election Day | Election Day | Register to vote in Washington |
| West Virginia | 21 days before Election Day | Postmarked 21 days before Election Day | 21 days before Election Day | Register to vote in West Virginia |
| Wisconsin | 20 days before Election Day | Postmarked 20 days before Election Day | Election Day | Register to vote in Wisconsin |
| Wyoming | N/A | Received 14 days before Election Day | Election Day | Register to vote in Wyoming |