The population count of Washington County, MD was 148,913 in 2014.


Population Change

Above charts are based on data from the U.S. Census American Community Survey | ODN Dataset | API - Notes:

1. ODN datasets and APIs are subject to change and may differ in format from the original source data in order to provide a user-friendly experience on this site.

2. To build your own apps using this data, see the ODN Dataset and API links.

3. If you use this derived data in an app, we ask that you provide a link somewhere in your applications to the Open Data Network with a citation that states: "Data for this application was provided by the Open Data Network" where "Open Data Network" links to Where an application has a region specific module, we ask that you add an additional line that states: "Data about REGIONX was provided by the Open Data Network." where REGIONX is an HREF with a name for a geographical region like "Seattle, WA" and the link points to this page URL, e.g.

Demographics and Population Datasets Involving Washington County, MD

  • API

    Choose Maryland: Compare Counties - Demographics | Last Updated 2017-03-23T14:42:20.000Z

    Population profile - total, rate of change, age, and density.

  • API

    Minority Business Enterprise: Statewide Directory - MBE, DBE (Disadvantaged Business Enterprise), SBE (Small Business Enterprise), and ACDBE (Airport Concession Disadvantaged Enterprise) Certified Businesses | Last Updated 2017-03-01T17:05:16.000Z

    MBE, DBE (Disadvantaged Business Enterprise), SBE (Small Business Enterprise) and ACDBE (Airport Concession Disadvantaged Enterprise) certified businesses are all shown. This dataset contains a list of businesses certified by Minority Business Enterprise (MBE) within the state of Maryland. This program is affiliated with the Maryland Department of Transportation (MDOT) Data are continually updated at MDOT's website for MBE: This dataset was created on Jan. 14 2016 and therefore shows all businesses certified as of that date. The Department of Information Technology (DoIT) will update this dataset using MDOT's source data, at least once per month moving forward. If you have questions about the dataset or data please contact

  • API

    WAOFM - Census - Population Density by County by Decade, 1900 to 2010 | Last Updated 2016-08-09T16:28:24.000Z

    Washington state population density by county by decade 1900 to 2010.

  • API

    Population Health Measures: Age-Adjusted Mortality Rates | Last Updated 2015-06-17T16:53:22.000Z

    Age-adjustment mortality rates are rates of deaths that are computed using a statistical method to create a metric based on the true death rate so that it can be compared over time for a single population (i.e. comparing 2006-2008 to 2010-2012), as well as enable comparisons across different populations with possibly different age distributions in their populations (i.e. comparing Hispanic residents to Asian residents). Age adjustment methods applied to Montgomery County rates are consistent with US Centers for Disease Control and Prevention (CDC), National Center for Health Statistics (NCHS) as well as Maryland Department of Health and Mental Hygiene’s Vital Statistics Administration (DHMH VSA). PHS Planning and Epidemiology receives an annual data file of Montgomery County resident deaths registered with Maryland Department of Health and Mental Hygiene’s Vital Statistics Administration (DHMH VSA). Using SAS analytic software, MCDHHS standardizes, aggregates, and calculates age-adjusted rates for each of the leading causes of death category consistent with state and national methods and by subgroups based on age, gender, race, and ethnicity combinations. Data are released in compliance with Data Use Agreements between DHMH VSA and MCDHHS. This dataset will be updated Annually.

  • API

    King County History Timeline | Last Updated 2015-04-24T21:09:04.000Z

    Milestones in the history of King County, Washington

  • API

    WAOFM - April 1 - Population by State, County and City, 1990 to Present | Last Updated 2016-06-30T18:17:22.000Z

    Intercensal and postcensal population estimates for the state, counties and cities, 1990 to present.

  • API

    Population and Economic Indicators | Last Updated 2016-11-18T18:52:00.000Z

    A set of basic demographic and economic data such as population, jobs, business licenses, income and poverty rate.

  • API

    Violent Crime & Property Crime by County: 1975 to Present | Last Updated 2017-03-09T17:03:13.000Z

    The data are provided are the Maryland Statistical Analysis Center (MSAC), within the Governor's Office of Crime Control and Prevention (GOCCP). MSAC, in turn, receives these data from the FBI's annual Uniform Crime Reports.

  • API

    King County Health Reform Indicators | Last Updated 2014-12-17T00:09:12.000Z

    Health reporting area (HRA) and zip code-level indicators for monitoring the impact of the Affordable Care Act in King County, WA. Topic areas range from access to care to population health. Imported to Socrata to allow data to be pulled as JSON from SODA to feed into Leaflet.js-based maps on an external site.

  • API

    Maryland Total Change in Resident Population: 2000-2013 | Last Updated 2016-11-30T14:37:56.000Z

    Total Change in Resident Population in Maryland and its Jurisdictions by year from 2000 to 2013