| |
| Age Group | Male | Female | Montana, 2010, Universe: 001 Total population Universe Population: 989,415 | ||
| Population | Pct | Population | Pct |  | |
| Total | 496,667 | 50.2 | 492,748 | 49.8 | |
| 0- 4 | 32,129 | 3.2 | 30,294 | 3.1 | |
| 5- 9 | 30,932 | 3.1 | 29,833 | 3.0 | |
| 10-14 | 31,620 | 3.2 | 29,504 | 3.0 | |
| 15-19 | 34,515 | 3.5 | 32,209 | 3.3 | |
| 20-24 | 34,939 | 3.5 | 32,199 | 3.3 | |
| 25-29 | 33,135 | 3.3 | 30,988 | 3.1 | |
| 30-34 | 30,209 | 3.1 | 28,532 | 2.9 | |
| 35-39 | 28,355 | 2.9 | 27,220 | 2.8 | |
| 40-44 | 28,848 | 2.9 | 28,522 | 2.9 | |
| 45-49 | 35,234 | 3.6 | 35,787 | 3.6 | |
| 50-54 | 38,747 | 3.9 | 40,064 | 4.0 | |
| 55-59 | 37,835 | 3.8 | 38,080 | 3.8 | |
| 60-64 | 32,124 | 3.2 | 30,819 | 3.1 | |
| 65-69 | 23,455 | 2.4 | 23,101 | 2.3 | |
| 70-74 | 16,806 | 1.7 | 17,380 | 1.8 | |
| 75-79 | 11,987 | 1.2 | 13,650 | 1.4 | |
| 80-84 | 8,781 | 0.9 | 11,561 | 1.2 | |
| 85+ | 7,016 | 0.7 | 13,005 | 1.3 | |