Inside TrustList's directory: 90,000+ listings, 200 categories, and where the concentration really sits

Open the category dropdown on TrustList and you're choosing from 200 of them. Add up every listing behind every one and the total is 90,346. Almost none of that is evenly spread.

Five categories — IT Service Providers, IT Product companies, Accounting Firms, Advertising companies and App Development companies — account for 50.4% of every listing on the platform. IT Service Providers alone holds 13,034, nearly 900 more than the next two categories combined.

The shape of the long tail

Below that top five, the numbers fall fast and then keep falling for a long time:

Rank	Category	Listings
1	IT Service Providers	13,034
2	IT Product companies	9,741
3	Accounting Firms	9,008
4	Advertising companies	7,269
5	App Development companies	6,511
6	Venture Capital firms	5,485
7	Digital Marketing companies	4,819
8	Business Service companies	4,074
9	Content Marketing Agencies	3,473
10	Design Agencies	3,467

Past the top ten, categories like Software Development (2,855), Investor (2,161) and Cloud Consulting (1,436) are still substantial. But 151 of the platform's 200 categories — three out of every four — hold fewer than 50 listings each. Artificial Intelligence Company sits at 837: a real, active category, but roughly one-sixteenth the size of IT Service Providers.

What that concentration actually means for a buyer

It is tempting to read "13,034 IT service providers" as depth. In practice it is closer to noise: at that scale, a directory listing on its own carries almost no filtering power, because almost everyone in the market has one. The categories doing useful narrowing work for a buyer are the mid-sized ones — the 500-to-2,000-listing range where Business Consulting (521), Conversion Optimization (614), Big Data & BI (767) and Artificial Intelligence Company (837) sit. A category of that size is large enough to have real competition, small enough that the differences between entries are still legible.

The long tail matters differently. A category with 40 or 80 listings is usually not thin because the market is small — it is thin because the category is new, specific, or recently split out from a broader one (this is exactly how "AI Model" exists as its own vertical rather than folding into "Artificial Intelligence Company": a distinct product type needs a distinct catalogue, not a subcategory of a services vertical). A tightly scoped long-tail category is often the fastest way to a short, relevant shortlist — the opposite of what its size suggests at a glance.

Why this is worth publishing rather than assuming

None of this is visible from inside any single category page — the concentration only shows up when you look at the whole catalogue at once, which is not something a buyer browsing "IT Service Providers" has any reason to do. It is, however, exactly the kind of structural fact a directory should be transparent about: what "13,034 listings" is actually telling you (very little, on its own) versus what a category of a few hundred is telling you (a genuine, navigable market).

The practical takeaway is simple. When a category count runs into five figures, treat the number as a sign to narrow — by sub-specialty, by size of client served, by geography — before treating any individual listing as a finalist. When a category sits in the low thousands or a few hundred, the count itself is doing real work, and the listings inside it are worth reading closely.

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Figures pulled from TrustList's live category index (type-listings, sorted by listing count) on 31 August 2026. 200 categories currently carry at least one published listing; the total across all of them is 90,346.