Ballot Processing and Election Security

Ballot Processing & Election Security

Lifecycle of a Ballot

Ballot Processing Infographic explaining the way a ballot gets processed

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Boulder County 24-hour ballot drop box

Election Security Community Briefing

Published in the fall of 2020, this report provides details about Boulder County’s approach to elections security and the actions we are taking to protect your voter information and the integrity of your vote.

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Pre-election Testing of the Ballots and Equipment

Boulder County Elections oversees strict testing and quality control of the ballot printing process. Our protocols go far beyond what is required by Secretary of State rule or state statute.

In addition to all the quality control we do while ballots are being printed, we are one of the only counties that uses live ballots during our pre-election testing of the ballots and equipment (every Colorado county performs a test called the Logic and Accuracy test before every election). This means we test vote on ballots pulled from the actual print run of ballots that will be mailed to voters, versus having the printer print a “separate test deck.” We then run the ballots through our scanners and use our voting system software to ensure everything is calibrated correctly and tabulating properly.

Examples of Ballot Printing Quality Control

Quality control processes that are conducted by the print vendor with oversight by Boulder County Election team members include (but are not limited to):

  • Ballot print alignment: Making sure all ballot styles are correctly printed, using a see-through mylar overlay to inspect every portion of the ballot and make sure all the text and target boxes are where they should be.
  • Checking fold lines: Making sure ballot fold lines are where they should be.
  • Verifying ballot styles: Making sure the right ballot styles are printed; that no files were mixed up/combined, etc.
  • Ensuring accurate ballot insertion: 2D bar codes are used on ballots and ballot envelopes to ensure that the ballot style inserted is correct for each voter.

This quality control work is done at the printer, prior to further testing of the ballots at our office through the ballot processing and voting system equipment.

Voting System Security

Our voting system is the equipment and software used to create ballots, capture votes, and tabulate results. The voting system we use is­­ called Dominion, one of the Colorado Voting Systems selected by the state after a rigorous public input process.

The voting system is not connected to the internet and there are no updates to the voting system once the “trusted build” is applied. The trusted build is the vendor software that is tested and certified by the Secretary of State’s office for election use.

Electronic voting machines

Boulder County does not use electronic voting machines (formerly referred to as DRE machines). Beginning in 2017, we do have “ballot marking devices.” These are available for any voter to use, and support accessible voting for disabled voters. The voter verifies their ballot choices onscreen, then prints a paper ballot and deposits the voted ballot into a secure ballot box before leaving the Voter Service and Polling Center. Only physical, paper ballots are used and counted in Boulder County.

Post-election Audit of the Election Results

To ensure voting system tabulation accuracy, a statewide risk limiting audit is conducted after each election. The process reviews how a ballot’s votes were captured at the time it was processed by comparing a sample of paper ballots with digital tallies. To learn more about the Colorado risk-limiting audit process, see this Politico story on the implementation, or this Colorado Public Radio story, or this FAQs page from the Colorado Secretary of State.

Elections Videos

Signature Verification Process

Mail Ballot Security

Elections Tour – Short Version

Elections Tour – Extended Version

Services at a Vote Center

Contact Us

Elections Division


303-413-7728 (Fax)
Boulder County Elections website

7:30 a.m. to 5 p.m.
Closed Fridays


Boulder: 1750 33rd St. (main office)
Map and Directions Boulder Location

Longmont: 529 Coffman St.*
Map and Directions Longmont Location

Lafayette: 1755 S. Public Road*
Map and Directions Lafayette Location
* Longmont and Lafayette locations only offer paper voter registration forms

Mailing Address

1750 33rd St., Suite 200
Boulder, CO 80301

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