Here is the 1999 D.C. United schedule. Please note that all times are ET and that the schedule is subject to change.
| Date | Opponent | Time (ET) |
| Sat. March 20 | at Tampa Bay | 7:00 p.m. |
| Sat. April 3 | at MetroStars | 7:00 p.m. |
| Sat. April 10 | at New England | 7:30 p.m. |
| Sat. April 17 | San Jose | 7:30 p.m. |
| Sat. April 24 | New England | 7:30 p.m. |
| Sat. May 1 | at Chicago | 8:00 p.m. |
| Sat. May 8 | MetroStars | 4:00 p.m. |
| Sat. May 15 | at Kansas City | 8:30 p.m. |
| Sat. May 22 | at Miami | 2:00 p.m. |
| Sat. May 29 | Chicago | 7:30 p.m. |
| Sat. June 5 | Columbus | 7:30 p.m. |
| Thu. June 10 | Miami | 7:30 p.m. |
| Sun. June 13 | at Columbus | 4:00 p.m. |
| Wed. June 16 | at Dallas | 8:30 p.m. |
| Sat. June 19 | Los Angeles | 7:30 p.m. |
| Sat. June 26 | Kansas City | 7:30 p.m. |
| Sun. July 4 | at San Jose | 7:00 p.m. |
| Wed. July 7 | at Columbus | 7:30 p.m. |
| Sat. July 10 | Colorado | 7:30 p.m. |
| Sun. July 25 | at New England | 1:00 p.m. |
| Sun. Aug. 8 | Tampa Bay | 2:00 p.m. |
| Wed. Aug. 11 | at MetroStars | 7:00 p.m. |
| Sat. Aug. 14 | Columbus | 4:00 p.m. |
| Sat. Aug. 21 | at Miami | 8:00 p.m. |
| Wed. Aug. 25 | Miami | 7:30 p.m. |
| Sat. Aug. 28 | at Colorado | 9:00 p.m. |
| Sat. Sept. 4 | Dallas | 7:30 p.m. |
| Fri. Sept. 10 | at Tampa Bay | 7:30 p.m. |
| Sat. Sept. 18 | MetroStars | 7:30 p.m. |
| Sat. Sept. 25 | at Los Angeles | 10:30 p.m. |
| Wed. Oct. 6 | Tampa Bay | 7:30 p.m. |
| Sat. Oct. 9 | New England | 7:30 p.m. |