Population in Marion, OH

Population in Marion, OH was 35,587 in 2025, according to the U.S. Census Bureau. That is up 0.2% from 2024. That is the 41st highest of 176 cities in 2025.

2025, persons35,587
Change on 2024+0.2%
Rank41st of 176Cities in Ohio ranked
Series high36,0572020
Series low35,3062022

Population in Marion, OH, 2020 to 2025

35.2K35.4K35.6K35.8K36K36.2K2020202120222023202420252020: 36,057 persons2021: 35,929 persons2022: 35,306 persons2023: 35,513 persons2024: 35,506 persons2025: 35,587 persons
persons. Source: U.S. Census Bureau, Annual estimates of the resident population for incorporated places, 1 July (Population Estimates Program, subcounty totals). Retrieved 2026-10-12, published 2026-05-14.
All 6 values
Periodpersons
202535,587
202435,506
202335,513
202235,306
202135,929
202036,057

Compared with Ohio and United States

Place2025
Marion, OH35,587
Ohio11,900,510
United States341,784,857

Rankings

Definition

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (Padrón). Norway: Statistics Norway, 1 January. United States: Census Bureau population estimates for 1 July. United Kingdom regions and local authorities: Office for National Statistics estimates for 30 June. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for incorporated places, 1 July (Population Estimates Program, subcounty totals). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-12.

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Questions

What is the population in Marion, OH?

Population in Marion, OH was 35,587 in 2025, according to the U.S. Census Bureau. That is up 0.2% from 2024. That is the 41st highest of 176 cities in 2025.

Where does this figure come from?

U.S. Census Bureau. Annual estimates of the resident population for incorporated places, 1 July (Population Estimates Program, subcounty totals). Retrieved by Invokely on 2026-10-12.

What was the highest population in Marion, OH?

36,057 in 2020, the highest value since 2020 in this series.

Population elsewhere in Ohio

All statistics for Marion, OH