| 100% | UNITED | 6 | It's the U in the UN |
| 71% | DDT | 3 | It's been banned in the U.S. since 1972 |
| 69% | NATO | 4 | The U.S. is in it |
| 69% | STCROIX | 7 | Denmark sold it to the U.S. in 1917 |
| 68% | LSD | 3 | The U.S. banned it in 1967 |
| 68% | LSD | 3 | The U.S. banned it in 1968 |
| 68% | WWII | 4 | The U.S. entered it in 1941 |
| 68% | WWI | 3 | The U.S. joined it in 1917 |
| 68% | WWII | 4 | The U.S. joined it in 1941 |
| 68% | OAS | 3 | The U.S. and Can. are in it |
| 68% | WWI | 3 | The U.S. joined it in 1917: Abbr. |
| 67% | HAVANA | 6 | The U.S.S. Maine sank in its harbor |
| 67% | ATM | 3 | It's called a cashpoint in the U.K. |
| 67% | KEROSENE | 8 | It's called paraffin oil in the U.K. |
| 67% | RUBELLA | 7 | It was eliminated from the U.S. in 2004 |
| 67% | DIAPER | 6 | It's called a "nappy" in the U.K. |
| 66% | OPEC | 4 | It imposed an embargo on the U.S. in 1973 |
| 66% | SYSTEM | 6 | It's the S in Apple's iOS |
| 66% | XENIA | 5 | Ohio city that's the largest in the U.S. that starts with its letter |
| 65% | SURINAME | 8 | It comes first in China, but second in the U.S. |
| 65% | HOUSE | 5 | It meets in the south wing of the U.S. Capitol |
| 65% | SYSTEM | 6 | It's the S in Apple's iOS technology |
| 65% | SYNDROME | 8 | It's the S in AIDS, IBS and PMS |
| 65% | OSAKA | 5 | With 1d, it's the name of the reigning US Open Champion in women's singles |
| 64% | HOFF | 4 | Harry S —, English author whose 1934 debut novel Trina was published in the US as It Happened in PRK |
| 64% | DRIVERSSIDE | 11 | It's on the left in the U.S. and the right in the U.K. |
| 64% | NHL | 3 | It first expanded to the US in 1924 |
| 64% | ALE | 3 | It's more than 4 percent alcohol by volume in the U.S. |
| 63% | TELAVIV | 7 | City from which the U.S. moved its embassy in 2018 |
| 63% | SCREEN | 6 | It's the S in cinema and television's SAG Awards |