So How Many Millennials Are There in the US, Anyway? (Updated)

CensusBureau-Share-of-Pop-by-Age-Group-Gender-Apr2016Marketers tend to focus a lot of energy on Millennials. Their lives are deconstructed on many different levels, and there’s research to be found on anything ranging from their top financial goals to the ways in which they use their phones. Those analyses are all helpful in their own right, but –  stepping back to the big picture for a moment – how many of these prized individuals are there in the US? The latest data out from the Census Bureau gives a sense of how large this coveted generation is.

[MarketingCharts has its own reports on Millennials. Check out our newest studies, both released this year: Marketing Financial Services to Millennials; and Marketing to Young City Solos.]

Before putting out some numbers, there are a few problems to take note of. Chiefly, there is no consensus definition of a Millennial; while 18-34 seems to be the most commonly used bracket (and one which doesn’t appear to change with each passing year!), other studies might use an 18-29 range or some other, making it necessary to identify age ranges when referring to this cohort. That’s why Pew Research’s declaration that there are now more Millennials than Baby Boomers makes sense in some light, but not in others. (The Washington Post does a great job of delving into that claim in this article, which also includes a useful interactive graphic.)

Meanwhile, it’s also worth noting that most Millennials don’t even identify as Millennials, and a young Gen Xer might feel more culturally similar to Gen Y. In other words, cultural and behavioral tendencies don’t tend to have fixed age breaks. (That’s why many argue that it’s more useful to look at personas rather than age brackets.)

Nevertheless, things being the way they are, marketers and researchers often look at age groups. So here’s a reference list of some commonly used age brackets and their corresponding population estimates and population shares as of July 1st, 2015.

  • 12-17: 25 million (7.8%)
  • 18-24: 31.2 million (9.7%)
  • 25-34: 44.1 million (13.7%)
  • 35-44: 40.6 million (12.6%)
  • 45-54: 43.2 million (13.4%)
  • 55-64: 40.9 million (12.7%)
  • 65-74: 27.6 million (8.6%)
  • 75+:    20.2 million (6.3%)

Some other popular age groups, including the ever-present 18-34 bracket:

  • 18-29: 53.7 million (16.7%)
  • 18-34: 75.4 million (23.4%)
  • 18-49: 136.8 million (42.6%)
  • 35-49: 61.4 million (19.1%)
  • 50-64: 63.2 million (19.7%)
  • 51-68: 72.3 million (22.5%)
  • 55+:    88.6 million (27.6%)
  • 65+:    47.8 million (14.9%)


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    For more on the important Baby Boomer demographic, see MarketingCharts’ report, “Advertising to Baby Boomers: The Why and How” [download page].

    Interested in a specific age or more detailed figures by group? Visit the interactive chart below and use the tooltips for exact figures, or download the Excel spreadsheet at the top of this article – which also provides gender breakdowns for each age – and sum up the specified ranges.

    A couple of fun facts to leave with:

    • As of July 1st last year, there were an estimated 76,974 centenarians (100+) in the US. Some 61,886 – or about 80% – of them were female; and
    • There were more males than females for each single year of age from newborn through age 35, but then more females than males for each single year of age from 36 on. The biggest disparity in favor of males was for 22-year-olds (133,920 more), while for females it was for 85-year-olds (208,259 more).