Research
What an SEO agency does, and how to tell a good one from a reseller
An SEO agency is hired to increase the qualified traffic a business earns from search. That used to mean one thing: rank higher on Google. In 2026 it means two, because in one survey of 1,076 B2B software buyers, 51% said they now start research in an AI chatbot more often than with Google, and the click economics behind ranking have changed. This is what the work involves, what it costs, and the questions that reliably separate an agency that measures something from one that sends a dashboard.
Key takeaways
- 51% of B2B software buyers now start research in an AI chatbot more often than with Google, up from 29% a year earlier.[1]
- 69% chose a different vendor than they originally planned because of a chatbot recommendation.[1]
- Where an AI Overview appears, the top-ranking page's clickthrough rate is 58% loweron average — a correlation, not a measured cause.[2]
- Only 38% of AI Overview citations come from pages in the organic top ten, down from about 76% in July 2025.[3]
What an SEO agency does#
An SEO agency is an outside team hired to increase the traffic a business earns from search without paying for each click. The work splits into four parts that have been stable for a decade: technical (can engines crawl, render and index the site), content (do pages answer what buyers search), authority (do other credible sites reference this one), and measurement (did any of it move).
A fifth part is new. Engines now answer directly instead of only listing links, so an agency is increasingly asked whether a brand appears inside those answers. That is a different job with different inputs, and most agency menus added it before their delivery caught up.
The three engagement models#
Retainer. A monthly fee for ongoing work. Standard for content and authority building, which compound slowly. The risk is that a retainer bills for activity whether or not anything moves.
Project or audit. A fixed-scope diagnostic with a deliverable. Useful when you want to know what is wrong before committing to a monthly spend. The risk is a report nobody implements.
Done-for-you implementation. The agency ships the changes rather than recommending them. More expensive per month, but it removes the failure mode where a correct fix list sits in a backlog for a year.
What changed in 2026#
Two things, both measured. First, where buyers start: G2 surveyed 1,076 B2B software buyers and found 51% now begin research with an AI chatbot more often than with Google, up from 29% the year before, and 69% ended up choosing a different vendor than they had planned because of what a chatbot said.[1]
Second, what a ranking is worth. Ahrefs found the presence of an AI Overview correlates with a 58% lower clickthrough rate for the top-ranking page, across 300,000 keywords.[2]Rankings can hold while traffic falls, which is why “we kept your positions” is no longer a sufficient report.
Questions that expose a weak agency#
“What will you measure, and how often?”AI answers vary between runs: the sources an engine cites overlap by only 34–42% between consecutive days.[5] An agency that reports a single before-and-after screenshot cannot tell improvement from noise. Ask for repeated runs per engine.
“Show me the fix list, not the score.” A visibility score is a thermometer, not a fix. Ask what changes on the site, who writes it, who ships it.
“Which keywords, and what is the difficulty?”Volume without difficulty is a vanity number. Note that difficulty scores are built from the backlink profiles of the pages currently ranking and, as Ahrefs states plainly, do not account for your own site's authority.[4] A low score is not a promise.
“What are you doing off our domain?” An agency that only edits your own pages is working part of the surface.
How much does SEO cost?#
There is no single rate, but the paid-search figures give a floor for how competitive the space is. In our own pull of Google Ads keyword-planner data for the United States, “seo agency” carries a cost per click around $46 and “digital marketing agency” around $24.[6] Agencies bid those prices to win a single client worth far more than the click.
The useful question is not the monthly number but what it buys: a report, or shipped changes and a re-measurement.
Related: what answer engine optimization involves, and what generative engine optimization actually costs. If you are evaluating one for a software company, we set out how we run this as a B2B SEO agency and as a SaaS SEO agency.
Want to see what an audit actually returns?
Sources
- G2, “The Answer Economy” — 1,076 B2B software buyers plus 39 interviews, surveyed March 2026, published April 2026.
- Ahrefs, “AI Overviews Reduce Clicks by 58%”— 150,000 keywords with an AI Overview vs 150,000 informational keywords without, February 2026. Correlational; vendor study.
- Ahrefs, “38% of AI Overview Citations Pull From The Top 10” — 863K keyword SERPs, 4M AI Overview URLs, March 2026. Vendor study.
- Ahrefs on Keyword Difficulty — states that KD is computed from referring domains to the top-10 pages and does not account for your own site's authority.
- “Don't Measure Once: Measuring Visibility in AI Search” — arXiv:2604.07585. Source sets overlap by 34–42% between consecutive days.
- Noetio, Google Ads keyword-planner data for the United States, pulled September 2026 via the DataForSEO search-volume endpoint. Our own measurement, not a third-party study.
Survey figures carry their sample sizes. Vendor studies are labelled, and the one figure that is our own measurement says so rather than borrowing a third party's authority.