SEO
Search engine optimization agencies and consultancies: 226 US firms that build organic visibility — technical health, content, authority, and now AI-search presence.
The wall
The SEO wall announces itself quietly: organic traffic flat for six quarters, competitors outranking the company for its own category terms, a site that was rebuilt for looks and lost its rankings, and a blog nobody reads because it answers questions nobody asks. It compounds slowly — which is why it is usually noticed years late.
What the discipline is
SEO firms build organic search visibility across four fronts: technical health (crawlability, speed, structure), on-page content matched to search intent, off-page authority (links and citations), and measurement. The discipline now extends past Google's blue links into AI-generated answers — optimizing so language-model search surfaces cite the company — sometimes labeled GEO (generative engine optimization) or AEO (answer engine optimization).
How vendors in this category work
SEO is sold almost entirely on monthly retainers, because rankings are cumulative: audits and fixes early, then a compounding cadence of content and authority work. Within this index's engagement data, SEO is one of the most review-covered categories — 190 of its 226 firms carry public ratings — and its firms cluster in the same $100–$199 hourly bands as the broader agency market.
The US SEO agency market at a glance
Questions buyers ask
Questions sourced from live Google "People Also Ask" data for this discipline (harvested August 2026); answers are The Wall's own.
What does an SEO agency do?
An SEO agency improves how visibly a site appears when buyers search. The work spans technical fixes (site speed, crawlability, indexing), keyword and intent research, content creation and optimization, authority building through links and mentions, and reporting that ties rankings to revenue rather than vanity metrics.
How much does an SEO agency typically cost?
US retainers commonly run from roughly $1,500 to $10,000+ per month depending on scope and competitiveness, with hourly consulting typically $100–$250. Those figures are consistent with this index’s broader agency data, where the most common disclosed hourly band is $150–$199 and most minimum project sizes sit at $10,000 or below.
Is SEO still worth it, or is it being replaced?
The discipline is evolving, not dying: organic search remains one of the largest sources of commercial traffic, and the rise of AI-generated answers adds a new surface to optimize for rather than eliminating the old one. The practical shift is that content now has to earn citations in AI answers as well as rankings in traditional results.
Can a company do SEO on its own?
The basics, yes: clear titles and descriptions, helpful content that answers real questions, and a Google Business Profile for local visibility. Where in-house effort typically stalls is technical remediation, competitive national keywords, and authority building at scale — the three areas where specialist firms earn their retainers.
Is it worth hiring an SEO agency?
It pays off when organic search is a meaningful acquisition channel for the category, leadership can commit at least one to two quarters before judging results, and the site has real technical or authority gaps an internal team cannot close. For a company with no search demand in its category, the same budget usually does more in another pillar.