How election security works: audits, paper trails, and testing

U.S. elections are run by thousands of state and local offices, each following layered procedures designed to make results verifiable. This guide describes the common categories of safeguards used across the country. The exact mix of practices varies by state and locality, so links to official sources are included throughout for readers who want to see how their own jurisdiction handles each step.

The layered approach

Election security is not a single mechanism. It is a stack of overlapping procedures — physical, technical, and administrative — applied before, during, and after voting. The Cybersecurity and Infrastructure Security Agency (CISA), which supports state and local election officials, describes election infrastructure and its protections at cisa.gov/topics/election-security. The U.S. Election Assistance Commission (EAC) provides voter-facing explanations of election administration at eac.gov/voters.

Paper records and paper trails

Most ballots cast in the United States are recorded on paper — either a hand-marked paper ballot or a paper record produced by a ballot-marking device. Paper records matter for security because they create a physical artifact of each vote that:

• Can be recounted by hand or by independent machines
• Can be compared against machine tallies during audits
• Does not depend on software to be read after the fact

Whether and how paper records are used, stored, and audited is governed by state law. Your state's election website, reachable through vote.gov, describes the equipment and records used where you live.

Testing before the election

Certification of voting systems

Voting systems are tested against standards before they are approved for use. The EAC administers a federal testing and certification program for voting systems, and states apply their own certification requirements on top of or alongside it. Details are available at eac.gov.

Logic and accuracy testing

Before each election, election offices conduct logic and accuracy (L&A) testing on the equipment that will be used. In general terms, officials run known sets of test ballots through the machines and confirm the equipment records and tallies them exactly as expected. Testing procedures — including whether sessions are open to public observation — are set by state and local rules. Many jurisdictions publish notices of their L&A testing; your local election office can tell you how it works in your area (usa.gov/election-office).

Chain of custody

Chain of custody refers to the documented control of ballots, equipment, and records at every step. Common elements include:

• Tamper-evident seals on equipment, ballot containers, and memory devices, with seal numbers logged and verified
• Two-person rules requiring more than one authorized person to handle or transport sensitive materials
• Access logs recording who handled materials, when, and why
• Secure storage for ballots and equipment before and after the election

These controls are designed so that any unauthorized access leaves evidence. Specific chain-of-custody requirements are defined by each state; CISA publishes general guidance on these practices at cisa.gov/topics/election-security.

Post-election audits

After voting ends, jurisdictions conduct checks to confirm that the reported results match the underlying records.

Traditional post-election audits

Many states require a review of a fixed percentage of precincts, machines, or ballots — for example, hand-counting the paper records from a sample and comparing them to the machine totals. The sample size and method are set by state law.

Risk-limiting audits

A risk-limiting audit (RLA) is a statistical method that examines a sample of paper ballots sized according to the reported margin: the closer the contest, the more ballots are checked. The audit is designed to provide a quantifiable level of statistical confidence that the reported outcome matches what a full hand count of the paper records would show, and it escalates — potentially to a full hand count — if the sample does not support the reported result. Which states use RLAs, and for which contests, varies and changes over time; check your state's election website via vote.gov or the EAC's resources at eac.gov.

Canvass and certification

Separately from audits, every jurisdiction conducts a canvass — a methodical reconciliation of ballot counts, voter check-ins, and returns — before results are certified as official. Election-night totals are always unofficial; certification follows the canvass on a schedule set by state law.

Other safeguards

• Voter registration list maintenance under federal and state law, so records are updated as voters move or become ineligible
• Physical and cyber security support for election offices, coordinated with agencies such as CISA
• Bipartisan or multi-party staffing and observation in many jurisdictions, so procedures are watched by people with competing interests in accuracy
• Public observation opportunities for testing, counting, and audits, as provided under state law

How to see these safeguards yourself

Most of these procedures are observable. Many election offices allow the public to watch logic and accuracy testing, central count operations, and audits, and some publish audit results online. Contact your local election office through usa.gov/election-office to learn what observation opportunities exist in your area.

Verify with official sources

Election procedures — equipment, testing, audit types, and observation rules — vary by state and locality and change over time. Confirm the specifics with your state or local election office. Find your local election office at usa.gov/election-office, and find your state's official election website through vote.gov.