Buchanan, ND has a population of 63 and is the 27,841st largest city in the United States. The population density is 827 per sq mi which is 8265% higher than the North Dakota average and 813% higher than the national average. The median age in Buchanan is 30 which is approximately 16% lower than the North Dakota average of 35. In Buchanan, 72% of the population over 15 years of age are married, 85% speak English and 0% speak Spanish. 98% of Buchanan residents were born in North Dakota, 2% were born out of state, 0% were born outside of the United States and 0% were foreign born.