Statistics

Agency Firm-Size and Headcount Distribution Statistics 2026

Quick answer

114,014 advertising-agency businesses operate in the US as of 2026, up 4.4% year over year and growing at a 6.7% compound annual rate since 2021, per IBISWorld. Those businesses collectively employ 325,536 people, growing at 5.8% average annual employment growth over the same period, which works out to an average of 2.9 workers per firm.

That 2.9-worker average is a mean, not a full establishment-size-band breakdown, so it can confirm that agencies skew small on average but cannot on its own support a claim like “X% of agencies have fewer than five employees.” A separate figure corroborates the same small-firm pattern from a different angle: 95% of professional-services firms are under 50 employees, per RSW/US’s 2025 survey, an agency-adjacent proxy rather than an agency-specific figure.

By VA Horizon Team · August 16, 2026 · 5 min read

The Headcount Bank, Sourced Line by Line

The figures below come from IBISWorld’s paid industry-research coverage of US advertising agencies, cross-referenced against a separate professional-services survey from RSW/US, each linked to its own source rather than repeated secondhand. Together they answer a narrower but more honest version of “how big is the average agency” than a single vague estimate.

Why One Average Can’t Tell the Whole Distribution Story

It’s worth stating plainly: a firm-wide average, in this case 2.9 workers per firm, is a mean pulled from dividing total employment by total business count, not a government establishment-size-band table showing the actual spread from solo operators up through large agencies. It answers “what does the typical firm look like on average” honestly, but it cannot answer “what share of agencies fall into a specific headcount bracket,” a distinction worth keeping in mind before repeating either figure as more precise than it is. Agency-count estimates themselves vary meaningfully by definition too, from roughly 41,250 on the low end to 120,000 to 134,000 on the high end depending on which research firm’s methodology is used, a further reason to treat any single headcount figure as directionally useful rather than a precise census.

The Numbers

325,536 people are employed across the US advertising-agency industry as of 2026, growing at 5.8% average annual employment growth from 2021 to 2026.

IBISWorld, Employment, Advertising Agencies in the US

Dividing total employment by total business count works out to an average of 2.9 workers per firm, IBISWorld’s own stated average-firm-size figure.

IBISWorld, Employment, Advertising Agencies in the US

95% of professional-services firms are under 50 employees, per RSW/US’s 2025 survey, an agency-adjacent proxy figure rather than an agency-specific breakout.

RSW/US, 2025 professional-services survey

Sources

The external data in this article draws on the sources below. Figures described in the text as estimates or industry triangulations are directional and are not attributed to a single dataset.

FAQ

How many marketing and advertising agencies are there in the US?

114,014 advertising-agency businesses as of 2026, up 4.4% year over year, per IBISWorld. Separate estimators using different definitions put the total anywhere from roughly 41,250 to 120,000 to 134,000, so treat any single count as methodology-dependent.

What is the average number of employees at a US marketing agency?

2.9 workers per firm, based on IBISWorld’s 325,536 total industry employees divided across its 114,014 counted businesses, both for 2026.

Does the 2.9-worker average mean most agencies have fewer than 3 employees?

Not necessarily. That figure is a mean, not a size-band distribution, so it confirms agencies skew small on average but cannot on its own support a specific claim about what share fall under any particular headcount threshold.

Is there other data confirming agencies are mostly small firms?

Yes. 95% of professional-services firms are under 50 employees, per RSW/US’s 2025 survey, an agency-adjacent proxy figure that corroborates the same small-firm pattern IBISWorld’s average points toward.

Why do different sources report such different total agency counts?

Definitional inconsistency. Estimates range from roughly 41,250 to 120,000 to 134,000 depending on how a given research firm defines and counts an “agency,” per MarketingScoop’s comparison, which is why this page treats IBISWorld’s employment-and-count pairing as the internally consistent figure to lead with.

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