Capital vs Capitol
Capital with an A has many meanings: a country's main city, a sum of money, an uppercase letter, or something of major importance. Capitol with an O is much narrower — it almost exclusively refers to a specific building where a legislature meets, especially the U.S. Capitol building or a U.S. state capitol.
Last reviewed on 2026-04-27.
Quick Comparison
| Aspect | Capital | Capitol |
|---|---|---|
| Spelling | -al ending | -ol ending |
| Main meanings | City, money, uppercase letter, important | A specific legislative building |
| Common contexts | "capital city," "working capital," "capital A" | "the Capitol," "state capitol" |
| In US usage | Washington is the capital | The Capitol is the building Congress meets in |
| Outside US | Same broad meanings | Rarely used (Westminster has "the Houses of Parliament," not a capitol) |
| Memory aid | Capital city — A for area | Capitol building — O for the round dome |
Key Differences
1. Many meanings versus one
Capital is a versatile word. It can mean: (1) the main city of a country or region (London is the capital of the UK); (2) money or other financial resources (working capital, venture capital); (3) the uppercase form of a letter (write your name in capitals); (4) of primary importance (a capital crime, of capital importance).
Capitol has essentially one meaning: a specific building where a legislative body meets. The U.S. Capitol in Washington, D.C., is the most famous; each U.S. state also has a capitol building.
2. Memory trick
Capital ends in -al: think of "all" — capital covers all the broader meanings (cities, money, letters, importance).
Capitol ends in -ol: think of the round O of the dome on the U.S. Capitol building. The O matches the architectural feature.
3. Origins
Both come from Latin caput (head). Capital is the older, broader meaning of "head" — the main thing, the most important.
Capitol comes specifically from the Capitoline Hill in Rome, where the Temple of Jupiter Optimus Maximus stood. The U.S. Capitol building was named in echo of that Roman heritage.
4. Worked sentences
"Tokyo is the capital of Japan." "They raised capital for their startup." "Begin proper nouns with a capital letter." "Murder is a capital offence in some jurisdictions."
"The protest gathered at the Capitol." "Each U.S. state has its own state capitol building." "Tours of the Capitol are available with reservation."
5. Where confusion arises
When discussing politics, both words can appear close together. "In the capital, the senator entered the Capitol." Both correct.
"The capitol of France is Paris" — wrong; should be "capital" (the city). Capitol refers to a building, not a city.
6. Outside the U.S.
Capital is used worldwide in all its meanings.
Capitol is a peculiarly American term. Other countries don't typically call their parliament buildings "capitols." The Houses of Parliament in London, the Bundestag in Berlin, and similar buildings have their own names.
When to Choose Each
Choose Capital if:
- Cities, money, letters, importance.
- "capital A," "working capital," "capital punishment."
- Anywhere outside the specific U.S. legislative-building context.
Choose Capitol if:
- The U.S. Capitol building or any U.S. state capitol.
- Specific architectural references to those buildings.
- Almost always with a capital C ("the Capitol") when referring to the federal building.
Worked example
A reporter writes: "In the U.S. capital, demonstrators gathered outside the Capitol to lobby Congress." Both words in one sentence: capital (the city, Washington, D.C.) and Capitol (the legislative building).
Common Mistakes
- "They mean the same thing." Capital is broad; capitol is narrow and refers specifically to a legislative building.
- "All government buildings are capitols." Capitol applies to specific U.S. legislative buildings, not government generally.
- "The capitol of England is London." The capital is London. England doesn't have a capitol building — its Parliament meets at the Houses of Parliament.