How do non-citizen voter registration rates compare in other states?
Executive summary
Available national data and mainstream sources focus on citizen voting-age population when reporting registration rates; the U.S. Census reports 73.6% of the citizen voting-age population was registered in 2024 (174 million people) but does not measure non‑citizen registration directly [1]. Reporting and academic debate exist: some groups claim substantial non‑citizen registration (Just Facts estimates 10–27% of adult non‑citizens registered) while government and journalistic sources emphasize safeguards and that routine federal/state statistics exclude non‑citizens from registration-rate denominators [2] [3] [4].
1. Official data measure citizens, not non‑citizens — the baseline
The U.S. Census and most mainstream datasets calculate registration and turnout based on the citizen voting‑age population (CVAP); the Census headline: 73.6% of CVAP were registered in 2024 and 65.3% voted, which means federal tabulations are explicitly excluding non‑citizens from the denominator and therefore do not provide state‑by‑state “non‑citizen registration rates” in their standard releases [1] [3].
2. Two competing narratives about non‑citizen registration
Public debate divides between those who say non‑citizen registration is negligible and those who estimate meaningful levels. The Brennan Center and similar researchers have argued that allegations of widespread non‑citizen voting are largely unfounded while noting voter‑roll errors occur (reported in Ballotpedia’s overview of the debate) [5]. By contrast, an advocacy research group, Just Facts, used a methodology to estimate that roughly 10%–27% of adult non‑citizens were illegally registered in the U.S., a range that would translate to about two million to five million registered non‑citizens given Census counts—an assertion that challenges mainstream assumptions and has been cited in public debate [2].
3. Why the data diverge: measurement and method matters
Differences come down to what is being measured and how. Official sources ask registrants to attest to U.S. citizenship on registration forms (and federal law requires a citizenship attestation) and most aggregate statistics use CVAP, which by design omits non‑citizens [4] [3]. Academic and advocacy studies that estimate non‑citizen registration typically cross‑reference survey reports, administrative records, or apply error‑adjustment methods to Census microdata—methods which can produce widely different estimates and are sensitive to assumptions about survey misreporting and administrative record linkage [2] [3].
4. State rules, automatic registration, and local variation affect risk and reporting
State practices vary in verification and access. Twenty‑four states and D.C. had automatic voter registration policies as of late 2025, a change proponents say reduces manual errors yet opponents argue it can introduce different verification challenges [5]. Some states require documentary proof of citizenship in certain circumstances while courts have limited blanket proof‑of‑citizenship rules for registration; Ballotpedia highlights that states have adopted mixed approaches, which shapes the pathways by which non‑citizens could end up on rolls [5] [6].
5. Local laws and isolated exceptions complicate the picture
A few municipalities and localities allow non‑citizen residents to vote in local elections (for example, certain Vermont towns, Takoma Park and some Maryland municipalities are noted instances), which creates pockets where non‑citizen registration is legal and appropriate — but these are narrow exceptions and do not reflect state or federal practice [6]. Most states and the federal government prohibit non‑citizen voting in federal elections and require a citizenship attestation on registration forms [6] [4].
6. What current reporting cannot tell us — and why transparency matters
Because primary federal and state statistical releases are built around CVAP and because states differ in record access and verification, available official sources do not provide a clean, comparable set of state‑level non‑citizen voter‑registration rates [3] [1]. Estimates like Just Facts’ rely on additional modelling and assumptions; they should be read as contested findings rather than settled facts [2]. Ballotpedia’s synthesis shows the debate is active and that claims on either side often rest on different data choices [5].
7. Bottom line for readers and policymakers
If your question is “how do non‑citizen registration rates compare by state?” the answer is: there is no authoritative, state‑by‑state official dataset measuring illegal non‑citizen registration because national statistics focus on citizens; the field is dominated by contested estimates and policy arguments [3] [1]. Policymakers and journalists must weigh conflicting studies, scrutinize methods, and account for state policy differences — and note that some localities explicitly permit non‑citizen voting in certain municipal contests, which is a legally distinct phenomenon from alleged illegal registration for federal elections [6] [5].
Limitations: available sources do not provide a definitive, comparable table of state‑level non‑citizen registration rates; they offer instead national CVAP‑based registration data and contested scholarly/advocacy estimates [1] [2].