| 59410 Augusta | 406 | Lewis and Clark County | Montana (MT) |
| 59633 Canyon Creek | 406 | Lewis and Clark County | Montana (MT) |
| 59625 Carroll College | 406 | Lewis and Clark County | Montana (MT) |
| 59623 City County Building | 406 | Lewis and Clark County | Montana (MT) |
| 59648 Craig | 406 | Lewis and Clark County | Montana (MT) |
| 59635 East Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59636 Fort Harrison | 406 | Lewis and Clark County | Montana (MT) |
| 59601 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59602 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59604 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59620 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59623 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59624 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59625 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59626 Helena | 406 | Lewis and Clark County | Montana (MT) |
| 59639 Lincoln | 406 | Lewis and Clark County | Montana (MT) |
| 59640 Marysville | 406 | Lewis and Clark County | Montana (MT) |
| 59620 State of Montana | 406 | Lewis and Clark County | Montana (MT) |
| 59648 Wolf Creek | 406 | Lewis and Clark County | Montana (MT) |