United States

The United States is a federal republic and a UN member state, classified under UN M49 code 840, with ISO alpha-2 code US and ISO alpha-3 code USA. The UN places it in the Americas region and Northern America subregion. The World Bank lists the seat of government as Washington, D.C. These identifiers come from the UN Statistics Division’s M49 standard and the World Bank country API. The M49 classification is a statistical coding system, not a political or territorial statement; it groups countries for data consistency and does not resolve sovereignty or border disputes.

Country Basics

The United States is a federal republic composed of 50 states, a federal district (Washington, D.C.), and several inhabited territories. Its UN M49 code is 840; its ISO alpha-2 code is US; its ISO alpha-3 code is USA. The UN classifies it under region Americas, subregion Northern America, and lists it as a UN member state. The World Bank’s capital field for the United States is Washington D.C. These codes and classifications are administrative labels used for statistics and communications, not political claims about borders or sovereignty.

Population

No single population number stays correct for long. The U.S. Census Bureau publishes official figures and projections; its latest releases are the most reliable primary source for a domestic count. The World Bank also publishes headcount data with a stated reference year, derived from UN Population Division work. For a stable citation, use the World Bank’s country API and note the reference year for the value you cite. Always state the source and the reference year when quoting a count, and treat census or survey data as historical snapshots rather than live totals.

Which Source to Use

The most authoritative domestic count is the U.S. Census Bureau’s decennial census, conducted every 10 years, plus annual updates between censuses. The UN Population Division publishes comparable cross-national figures and projections, updated periodically. The World Bank’s population indicator (SP.POP.TOTL) also provides annual numbers. All three sources differ slightly because they use different definitions, reference dates, and estimation methods. Always name the source and the reference year when quoting a figure. For a domestic snapshot, use the Census Bureau’s Population Clock or annual releases; for cross-country comparison, use the UN World Population Prospects or the World Bank API.

How to Read the Numbers

Census and survey figures are estimates, not exact counts, and are revised after each decennial census. The 2020 census counted 331,449,281 residents. The Census Bureau’s mid-2024 estimate was approximately 335 million. The UN’s 2024 revision gives a different figure because it uses different definitions and estimation methods. For any number, state the source and reference date.

Seat of Government

The seat of government is Washington, D.C. The World Bank capital field for the United States lists Washington, D.C. This is a statistical and administrative classification, not a territorial or political claim. The District of Columbia is not a U.S. state, and its residents do not have voting representation in Congress. The U.S. Constitution does not designate a formal national seat; Washington, D.C. functions as the de facto seat. If you are comparing capital cities across countries, check the source definition of “capital” for each country because some nations designate administrative, legislative, and judicial seats in different cities.

Official Language

The United States has no official language at the national level. English is the de facto national language. Many states have passed official-English laws, but the federal government has not designated any language as official. According to the U.S. Census Bureau’s 2019 American Community Survey, roughly 78% of residents aged 5 and older spoke only English at home; Spanish was the most common non-English language, spoken by about 13% of that group. Some states recognise additional languages, including Hawaiian in Hawaii and Indigenous languages in Alaska. For current language statistics, consult the U.S. Census Bureau’s American Community Survey tables (S1601) and cite the release year. The ACS is a survey, not a census; its estimates carry margins of error.

Currency

The currency is the US dollar (USD, code 840). The US Bureau of Engraving and Printing and the US Mint produce currency; the Federal Reserve manages monetary policy. Exchange rates are set in foreign-exchange markets and change continuously. For a current value, check the Federal Reserve or a central bank reference rate. Do not rely on a static conversion in this guide.

Political System

The United States is a federal republic with a presidential system. The national government has three branches: executive (President), legislative (Congress), and judicial (Supreme Court). The country is a constitutional republic with 50 states, a federal district (Washington, D.C.), and several territories. The two dominant political parties are the Democratic Party and the Republican Party. The sitting President is Joe Biden (as of 2025). The next presidential election is scheduled for November 2028. The sitting Congress is the 119th. For current leadership and government structure, consult official U.S. government sources, not third-party summaries.

Key Data Sources

Reference year for this profile is 2025. Use the World Bank API as the baseline for economic and development indicators. Use the U.S. Census Bureau for demographic snapshots. Use the U.S. State Department and U.S. Citizenship and Immigration Services (USCIS) for visa and entry requirements. Use the U.S. Bureau of Labor Statistics (BLS) for labor market data. Use the U.S. Bureau of Economic Analysis (BEA) for GDP and national accounts. Use the U.S. Energy Information Administration (EIA) for energy statistics. Use the Federal Reserve for monetary data. Use the U.S. Department of the Treasury for federal fiscal data. Use the U.S. Centers for Disease Control and Prevention (CDC) for health statistics. Use the U.S. Department of State for travel advice. Use USCIS for visa and immigration policy.

Definitions

A country profile is a structured summary of a country’s key attributes, geographic, demographic, economic, political, and cultural, that enables comparison across countries. A statistical classification is a standardized coding system used by international organizations to group countries into regions and categories. The UN M49 classification is a standard numeric coding system developed by the United Nations Statistics Division to identify countries and regions. A reference year is the year for which a given data point was measured or estimated; always cite it. A country comparison is the act of placing two or more countries side by side on a set of attributes to identify similarities and differences, not to rank them as better or worse.