How have Muslim population percentages in US states changed over the past two decades?
Executive summary
U.S. Muslim share of the population has risen but disagreement about its size and state-level change persists: Pew projects the national share from 0.8% in 2010 to 1.7% by 2030 (projection) while the 2020 U.S. Religion Census counted about 4.5 million Muslims, a figure advocates and other compilations use for state estimates [1] [2]. Public-facing compilations list the largest state totals in New York, California and Illinois—New York often appears near 700–725k Muslims—yet sources and methods vary, producing wide state‑level differences [3] [4].
1. Biggest-picture growth: steady national increase, uncertain magnitude
Scholars and advocacy groups agree Muslim numbers in the U.S. have grown substantially over recent decades, driven mainly by immigration, higher fertility among some immigrant groups, and conversions [5] [6]. Pew’s national projection—0.8% in 2010 rising to 1.7% in 2030—frames the expected doubling of the Muslim share over two decades, but that is a projection based on demographic models rather than a direct state‑by‑state census [1]. The Oxford Research Encyclopedia likewise states Muslims are “little more than 1 percent” of the U.S. population today, confirming growth but underscoring that the exact share depends on source and method [5].
2. Conflicting counts: surveys, religion census and advocacy estimates
Estimates diverge widely. A 2020 United States Religion Census estimate cited by multiple outlets places the Muslim population around 4.5 million and is the basis for many state totals; other surveys—for example older Pew telephone surveys—produced smaller national counts (around 2.35 million in some past Pew work), and advocacy groups have argued for still higher totals [2] [7] [8]. The practical consequence is that state‑level percentage changes over 20 years will look different depending on which baseline you choose: projections, survey estimates, or the religion census [2] [1] [7].
3. Where Muslims are concentrated and which states changed most
Available state compilations consistently put New York, California and Illinois among the states with the largest Muslim populations—New York figures frequently cited near 724,475, California around 504,056, and Illinois also in the top tier—followed by New Jersey and Texas in many rankings [3] [4]. These are raw-population tallies rather than percentage shares; they reflect metropolitan concentration patterns and immigration settlement, not uniform statewide diffusion [3] [4].
4. Percentages vs. raw counts: how to read change
State percentage change matters more for political and social impact than raw counts, but the sources provided do not supply a standardized, comparable time series of state percentages for 2005/2010/2020. Pew’s national share projection gives a benchmark for nationwide percentage change (0.8%→1.7% by 2030) but does not map every state’s percentage trajectory in the supplied reporting [1]. Compilations that list state totals do so using different inputs and years, so they can imply change without a comparable two‑decade baseline [3] [4].
5. Why sources disagree: methodology and incentives
Differences stem from survey design (phone vs. faith‑community census), self‑identification versus institutional counts, and the political interests of data users. Muslim organizations have long argued that surveys undercount their communities and have mounted their own tallies; media and demographic sites combine religion‑census output, Pew projections, and other data streams—producing inconsistent state figures [7] [2] [3]. Pew and academic outlets emphasize transparent modeling but accept wider error margins for small populations; advocacy groups emphasize higher counts to signal political presence [1] [7].
6. What’s missing and how to get a clearer picture
Available sources do not provide a consistent, comparable two‑decade state‑by‑state percentage series in the material you supplied—so precise percentage changes for every state over the last 20 years are not present in current reporting (not found in current reporting). For rigor, combine the 2000/2010/2020 U.S. Religion Census outputs, Pew state estimates and consistent survey series; where those are unavailable, report ranges and explicitly note methodology (available sources do not mention a single authoritative state‑by‑state series covering 2005–2025).
7. Practical takeaways for readers and policymakers
Expect continued growth in absolute numbers and modest rises in state shares concentrated in metro areas, but treat any single headline number with caution: whether Muslims are “1%,” “2%,” or several million in a state depends on source choice [5] [2] [3]. Use multiple datasets, disclose methods, and treat state‑level percentage change as provisional until researchers publish harmonized, reproducible time series [1] [2].
Limitations: this analysis relies exclusively on the supplied materials, which mix projections, religion‑census totals and third‑party compilations with varying methods; definitive, comparable state‑by‑state percentage trends over the past 20 years are not present in these sources (not found in current reporting).