What is the current federal age of majority in the United States?

1. What the record of claims actually says — a clear extraction of the competing statements

Analyses provided converge on two clear, testable claims: first, there is no federal age of majority that applies nationwide; second, the modal age of majority across U.S. states is 18, with specific exceptions. The Legal Information Institute and several state-by-state summaries explicitly state that most states and Washington, D.C., use 18 as the age of majority, while naming Alabama and Nebraska at 19 and Mississippi at 21 ^{[2] [1]}. Another analysis points out that some resources describe the concept without endorsing a single federal number, underlining that age-of-majority determinations are matters of state law ^[4]. These two threads—state control and 18 as the common standard—are the anchors for all subsequent factual comparisons.

2. The state-by-state reality — why 18 predominates and where the outliers sit

The practical map of adulthood in the U.S. is dominated by the near-universal adoption of 18 as the threshold for the age of majority; 47 states and D.C. are routinely reported at 18, and primary legal summaries reflect that pattern ^[1]. The remaining states are the outliers: Alabama and Nebraska legally mark majority at 19, while Mississippi retains 21 as its statutory majority age according to widely cited compilations ^{[2] [1]}. Several state codes, such as Maryland’s statutory definition setting majority at 18, exemplify the granular, jurisdictional nature of the rule—each state’s statutes and case law define when parental authority ends and an individual can exercise adult civil powers ^[5]. The bottom line is that the age of majority is almost always 18, but you must check state law for exceptions ^[1].

3. Federal overlay — where the federal government sets age limits and where it does not

Federal law does not establish a blanket age of majority; nevertheless, the federal government has set age thresholds for particular federal rights and responsibilities. The clearest federal intervention is the Twenty-sixth Amendment, ratified in 1971, which guarantees the right to vote at 18 in federal and state elections ^[3]. Federal statutes and regulations also impose age-based limits for areas such as military enlistment, firearm purchases, and Social Security eligibility, but these operate alongside and sometimes in tension with state majority rules. Analysts emphasize that when federal law prescribes an age for a specific right, that federal standard governs that narrow subject even if the state’s age of majority differs ^{[6] [7]}. Thus federal rules exist for particular domains, not for legal majority generally.

4. The practical consequences — why these distinctions matter in everyday life

Differences in age-of-majority rules affect concrete legal capacities: the ability to enter contracts, sue or be sued without a guardian, consent to medical treatment, and be prosecuted or sentenced as an adult. When a state treats someone as a minor past 18, parental duties and statutory protections can remain, which alters liability and access to services ^[2]. Conversely, federal voting rights and some federal program eligibilities at 18 grant national-level adulthood for those specific purposes ^[3]. Analysts note that inconsistency creates friction for people who move between states, for businesses that contract across state lines, and for courts interpreting capacity when federal and state ages diverge ^[4]. The key takeaway is that the nominal age of adulthood is more than academic—it has tangible legal and civic effects ^[1].

5. Multiple viewpoints and potential agendas — interpreting the law versus advocating change

Sources fall into two camps in emphasis: legal reference works and advocacy or explanatory outlets. Legal reference sources prioritize statutory accuracy and underscore state variation, which frames the issue as a technical, jurisdictional matter ^{[2] [6]}. Advocacy-oriented or public-facing summaries stress the practical standard that most adults are 18 and highlight the inconsistency as a policy problem needing reform, especially where states lag at 19 or 21 ^{[1] [7]}. When outlets emphasize uniformity, the implicit agenda is policy harmonization; when they stress state autonomy, the agenda is preserving local control. Both framings are factual—either focusing on the dominance of 18 or on the exceptions—but readers should note the underlying policy preferences influencing emphasis ^{[4] [1]}.

6. Bottom line and where to verify the rule for a particular case

The established factual bottom line is: there is no single federal age of majority; most states set it at 18, with Alabama and Nebraska at 19 and Mississippi at 21, and the 26th Amendment guarantees voting at 18 ^{[1] [2] [3]}. For any specific question—contract validity, medical consent, or criminal status—consult the relevant state statute or an up-to-date state code, because applicability depends on jurisdiction-specific language and sometimes court interpretation ^{[5] [4]}. If you need case-specific verification, identify the state involved and check that state’s statutes or an authoritative state-compiled summary; the cited analyses provide the national lay of the land but do not replace consulting the controlling state law ^[5].