What are projections for Muslim American population growth due to fertility?

1. Projections that drive headlines: doubling and becoming a much larger minority

Pew’s modeling framework projects the number of Muslims in the United States to more than double from about 2.6 million in 2010 to roughly 6.2 million by 2030, a change Pew attributes largely to immigration and higher-than-average fertility among Muslims ^{[2] [3]}; more recent Pew reporting indicates the Muslim population has continued to grow at roughly 100,000 people per year in the 2010s and 2020s, driven by natural increase (births minus deaths) and migration ^{[6] [7]}.

2. How fertility factors into those projections

Pew’s projections explicitly incorporate differential fertility: globally and in the U.S., Muslim populations tend to be younger and have higher fertility rates than non-Muslims, which raises the number of births and accelerates population growth even where conversion plays a smaller role ^{[1] [2] [8]}; in a U.S. survey measure of “completed fertility,” Muslim adults ages 40–59 reported an average of about 2.4 children versus an American average of about 2.1, a gap that helps explain part of the projected growth ^[7].

3. Models, inputs and what “due to fertility” really means

Pew’s long-range projections are not simple extrapolations of current population counts but models that combine current group sizes, age structures, fertility and mortality rates, migration flows and religious switching to estimate future numbers — so the phrase “due to fertility” means fertility is a modeled driver, not that fertility alone will produce the entire increase ^[1]; the same methodology underlies global projections showing Islam as the fastest-growing major religion largely because of higher fertility and a youthful age profile ^{[1] [8]}.

4. Limits, uncertainty and missing data

There is no single, direct measure of total fertility for Muslims in the U.S. because the U.S. Census does not ask religion, forcing demographers to estimate fertility from subgroup data (foreign‑born vs. U.S.-born Muslims) and surveys, which introduces uncertainty and potential bias into projections ^{[4] [3]}; moreover, federal population forecasts demonstrate that changing fertility and immigration assumptions materially alter long-term outcomes, meaning a future drop in Muslim fertility or reduced immigration could slow the projected rise ^[5].

5. Alternative scenarios and policy sensitivity

Projections that emphasize fertility assume current differentials persist; if Muslim fertility rates converge downward toward the U.S. average — as has occurred in many Muslim‑majority countries as education and urbanization rise — or if net immigration declines, the pace of Muslim American growth would slow, a contingency reflected in Pew’s note that growth is expected to decelerate by 2030 as fertility gaps narrow and immigration’s share falls ^{[3] [1]}; conversely, continued high immigration would sustain faster growth, which is why analysts stress migration policy and demographic change together shape the outcome ^{[6] [5]}.

6. Bottom line for “projections due to fertility”

Credible demographic work indicates that higher fertility among Muslims in the U.S. is an important and measurable contributor to projected population increases — enough that Pew models show a doubling to ~6.2 million by 2030 and sustained growth thereafter — but those projections are contingent on assumptions about fertility persistence, migration and age structure and are constrained by incomplete direct fertility data for U.S. Muslims ^{[2] [6] [7] [3]}.