The alcohol laws of the United States regarding minimum age for purchase have changed over time. In colonial America, generally speaking, there were no purchase ages, and alcohol consumption by young teenagers was common, even in taverns. In post-Revolutionary America, such freedom gradually reduced due to religious sentiments (as embodied in the temperance movement) and a growing recognition in the medical community about the dangers of alcohol. The more modern history is given in the table below. Unless otherwise noted, if different alcohol categories have different minimum purchase ages, the age listed below is set at the lowest age given (e.g. if the purchase age is 18 for beer and 21 for wine or spirits, as was the case in several states, the age in the table will read as "18", not "21"). In addition, the purchase age is not necessarily the same as the minimum age for consumption of alcoholic beverages, although they have often been the same.

As one can see in the table below, there has been much volatility in the states' purchase ages since the repeal of Prohibition in 1933. Shortly after the ratification of the 21st amendment in December, most states set their purchase ages at 21 since that was the voting age at the time. Most of these limits remained constant until the early 1970s. From 1969 to 1976, some 30 states lowered their purchase ages, generally to 18. This was primarily because the voting age was lowered from 21 to 18 in 1971 with the passing into law of the 26th amendment. Many states started to lower their minimum purchase age in response, most of this occurring in 1972 or 1973. Twelve states kept their purchase ages at 21 since repeal of Prohibition and never changed them.

From 1976 to 1983, several states voluntarily raised their purchase ages to 19 (or, less commonly, 20 or 21), in part to combat drunk driving fatalities. In 1984, Congress passed the National Minimum Drinking Age Act, which required states to raise their ages for purchase and public possession to 21 by October 1986 or lose 10% of their federal highway funds. By mid-1988, all 50 states and the District of Columbia had raised their purchase ages to 21 (but not Puerto Rico, Guam, or the Virgin Islands, see Additional Notes below). South Dakota and Wyoming were the final two states to comply with the age 21 mandate. The current purchase age of 21 remains a point of contention among many Americans, because of it being higher than the age of majority (18 in most states) and higher than the purchase ages of most other countries. The National Minimum Drinking Age Act is also seen as a congressional sidestep of the Tenth Amendment. Although debates have not been highly publicized, a few states have proposed legislation to lower their purchase age, while Guam raised its purchase age to 21 in July 2010.

State Pre-Prohibition(prior to 1919) Post-Prohibition(after 1933) 1970s / 26th Amendment(adopted in 1971) 1980s / Drinking Age Act of 1984 21st century Alabama Pre 1881:None1881:21 (none with consent of parent) 21 1975:Lowered to 19 1986:Raised to 21 21 (no one underage is allowed consumption Section 28-1) Alaska N/A 21 1970:Lowered to 19 1984:Raised to 21 with grandfather clause (if born before January 1, 1965) 21 (unless the underage person is not on a licensed premises and the alcoholic beverage is provided by a parent, legal guardian, or spouse over the age of 21) Arizona N/A 21 1972:Lowered to 19New York Times, December 4, 1972, "State Braces for Lowering Drinking Age to 18 Jan. 1" (NYT online archive) 1985:Raised to 21 21 Arkansas Pre 1925:None1925:21 21 21MINIMUM DRINKING AGE LAWS, 1990 21 21 California Pre 1891:Regulated by municipality/county (common age was 16)1891:18 (statewide) 1933:21 21 21 21 (except small amounts for religious ceremonies) Colorado None (Dec) 1945:18: for 3.2% near-beer21: for wine and liquor 18 for 3.2% beer; 21 for wine and liquor Raised to 21 on Jul 31 1987 (with grandfather clause) 21 Connecticut 21 21 1972:Lowered to 18OLR Research Report-Lowering the Drinking Age, 2009. Cga.ct.gov. Retrieved on 2011-06-22. 1982:Raised to 191983:Raised to 201985:Raised to 21U.S. Department of Transportation final report (DOT HS 809 348) "Determine Why There Are Fewer Young Alcohol-Impaired Drivers," section III.B., 21 (exemptions: (1) a person over age eighteen who is an employee or permit holder under section 30-90a and who possesses alcoholic liquor in the course of such person's employment or business, (2) a minor who possesses alcoholic liquor on the order of a practicing physician, or (3) a minor who possesses alcoholic liquor while accompanied by a parent, guardian or spouse of the minor, who has attained the age of twenty-one. Nothing in this subsection shall be construed to burden a person's exercise of religion under section 3 of article first of the Constitution of the state in violation of subsection (a) of section 52-571b. Delaware N/A 21 1972:Lowered to 20 1984:Raised to 21 21 District of Columbia N/A 18: for beer and wine21: for liquor 18: for beer and wine21: for liquor 1986:Raised to 21 with grandfather clause. 21 Florida N/A 21 1973:Lowered to 18 1980:19 1986:Raised to 21 with grandfather clause 21 Georgia N/A 21 1972: Lowered to 18 1982:Raised to 191985:Raised to 201986:Raised to 21 21 Hawaii N/A 21 1972:Lowered to 18 1986:Raised to 21 21 Idaho N/A 20: for beer21: for wine and liquor 1972:Lowered to 19 (all) 1987:Raised to 21 in 1987 (Apr 11) with grandfather clause 21 Illinois 1872:Age of majority (none with written consent of parent)pre 1961: Age of majority 1961: Raised to 21Chicago Daily Tribune, August 3, 1961, "Girl, 19, sues for right to have a drink" (ProQuest archive) 1973:Lowered to 19: for beer and wine21: for liquorChicago Tribune, June 14, 1973, "Beer at 19 Signed by Walker." (ProQuest archive) 1980:Raised to 21"History of DUI Laws In Illinois", Illinois Secretary of State website 21 Indiana N/A Post-1934:21 21 21 21 Iowa N/A 21 1972:Lowered to 19 in 1972 (Jul 1)1973:Lowered to 18 in 1973 (Jul 1)1978:Raised to 19 in 1978 (Jul 1) 1986:Raised to 21 in 1986 (Jul 1) with grandfather clause. 21 Kansas N/A 1949:18: for beer and wine with less than 4% ABV21: for liquor 18: for beer and wine with less than 4% ABV21: for beer and wine with 4% ABV or more21: for liquor 1985:Raised to 21 21 (However, anyone under 21 may consume cereal malt beverages with parental supervision on their own property) Kentucky N/A 1938:21 21 21 21 Louisiana None 18 18 1987:Raised to 21 de jure in 1987,but de facto age was still 18 until 1995 due to a sale loophole.1995:De facto age raised to 21 in 1995 when loophole was closed.1996:In 1996, briefly lowered by Louisiana Supreme Court to 18 until it reversed its decision, raising to 21 three months later.Other exceptions still remain. Exceptions to Minimum Age of 21 for Possession of Alcohol as of January 1, 2010, Alcohol Policy Information System21 (Exceptions to state law include): *Religious purposes;

*When accompanied by a parent, spouse, or legal guardian 21 or over;

*For medical purposes;

*In a private residence, including up to 20 acres;

*The sale, handling, transport, or service of alcoholic beverages in lawful ownership of an establishment or lawful employment of a person under 21 by a licensed manufacturer, wholesaler, or retailer. Maine N/A 211969:Lowered to 20 1972:Lowered to 181977:Raised to 20 1985:Raised to 21 21 (however minors can drink at home with parental supervision) Maryland N/A 21 1974:Lowered to 18: for beer and wine21: for liquorThe Years of the Rat. Magazine.loyola.edu (2009-08-18). Retrieved on 2011-06-22.Effects of Drunk Driving . Drivingdrunk.org. Retrieved on 2011-06-22. 1982:Raised to 21 with grandfather clause for those born June 30, 1964, or earlier 21 (however anyone can drink when parents, spouses, teachers are present) Massachusetts N/A 21 1973:Lowered to 181979:Raised to 20 in 1979 (Apr 16) Raised to 21 in 1985 (with grandfather clause) 21 Michigan N/A 21 1972:Lowered to 18 in 1972 (Jan 1)Chicago Daily Defender, January 4, 1972, "Drinking age lowered in Michigan" (ProQuest archive). 1978:Raised to 19 in 1978 (Dec 3)1978 State Ballot Issues. (PDF) . Retrieved on 2011-06-22.Daily Collegian, March 16, 1979, "Pennsylvania drinking age follows national trend." (Penn State library ActivePaper online archive )1978:Raised to 21 in 1978 (Dec 21), 18 days later.First state to raise age to 21 since it was lowered 21 Minnesota N/A 21 1973:Lowered to 18 (June 1)1976:Raised to 19 (Sept 1)Resources on Minnesota Legislative Issues, Legal Age in Minnesota, 2009 . Leg.state.mn.us. Retrieved on 2011-06-22.First state to raise age after lowering. 1986:Raised to 21Twin Cities.com, Pioneer Press, August 20, 2008 – B8 Editorial, "A lower legal drinking age?" (twincities.com website) 21 Mississippi ? 1966:18: for beer and wine21: for liquor(alcohol not legalized until 1966) 21 Raised to 21 in 1986 21 Missouri ? 1945:21 21 21 21 Montana ? 21 1971:Lowered to 191973:Lowered to 18Platform plank: Dems want to lower drinking age to 18. Helenair.com (2008-07-27). Retrieved on 2011-06-22.1979:Raised to 19 1987:Raised to 21New York Times, March 10, 1987, "Drinking age is fiery issue in West" (ProQuest archive). 21 Nebraska ? 21"Drinking Age History" , Nebraska Liquor Control Commission1969:Lowered to 20 1972:Lowered to 19 1980:Raised to 201985:Raised to 21 21 Nevada ? 1933:21 21 21 21 New Hampshire ? 21 1973:Lowered to 181979:Raised to 20 1985:Raised to 21 21 New Jersey Before 1880:NonePost-1880:18 (penalties only against businesses) 21 1973:Lowered to 18 1980:Raised to 191983:Raised to 21 21 (As of February 22, 2021, there are no longer any penalties for underage drinking besides warnings.) New Mexico ? 1934:21 21 21 21 New York 18 (16 before 1896) Initially 21 immediately after Prohibition, then reduced to 18 four months later. 18 1982:Raised to 19 in 1982 (Dec)1985:Raised to 21 in 1985 (Dec) 21