This is a list of films which placed number one at the weekly box office in the United States during 1943 per Variety's weekly National Boxoffice Survey. The results are based on a sample of 20-25 key cities and therefore, any box office amounts quoted may not be the total that the film grossed nationally in the week.
| † | This implies the highest-grossing movie of the year. |
| Date | Title | Ref |
|---|---|---|
| January 6 | Road to Morocco | [1] |
| January 13 | [1] | |
| January 20 | [1] | |
| January 27 | Casablanca | [1] |
| February 3 | [2] | |
| February 10 | [2] | |
| February 17 | [2] | |
| February 24 | [2] | |
| March 3 | [3] | |
| March 10 | [3] | |
| March 17 | [3] | |
| March 24 | [3] | |
| March 31 | [3] | |
| April 7 | [4] | |
| April 14 | [4] | |
| April 21 | [4] | |
| April 28 | The Human Comedy | [4] |
| May 5 | [5] | |
| May 12 | [5] | |
| May 19 | [5] | |
| May 26 | [5] | |
| June 2 | [6] | |
| June 9 | [6] | |
| June 16 | [6] | |
| June 23 | [6] | |
| June 30 | [6] | |
| July 7 | [7] | |
| July 14 | [7] | |
| July 21 | [7] | |
| July 28 | [7] | |
| August 4 | [8] | |
| August 11 | [8] | |
| August 18 | This Is the Army † | [8] |
| August 25 | [8] | |
| September 1 | [9] | |
| September 8 | [9] | |
| September 15 | [9] | |
| September 23 | [9] | |
| September 30 | [9] | |
| October 6 | [10] | |
| October 13 | [10] | |
| October 20 | [10] | |
| October 27 | For Whom the Bell Tolls | [10] |
| November 3 | This Is the Army † | [11] |
| November 10 | [11] | |
| November 17 | So Proudly We Hail! | [11] |
| November 24 | [11] | |
| December 1 | This Is the Army † | [12] |
| December 8 | [12] | |
| December 15 | [12] | |
| December 22 | [12] | |
| December 29 | The Song of Bernadette | [12] |