Marmarth
- County:
- Slope County
- County Seat:
- No
- Area (mi²):
- 2.578
- State:
- North Dakota
Marmarth is a city located in Slope County, North Dakota. Marmarth has a 2026 population of 94. Marmarth is currently declining at a rate of -2.08% annually and its population has decreased by -6% since the most recent census, which recorded a population of 100 in 2020.
The median household income in Marmarth is $62,813 with a poverty rate of 4%. The median age in Marmarth is 61.3 years: 61.7 years for males, and 49.9 years for females. For every 100 females there are 127.3 males.