“How much does SEO cost?” is one of the most-searched marketing questions in the UK, and one of the worst answered. Page one is a mix of agencies quoting a monthly figure with no scope, and listicles asserting averages that do not survive contact with a real quote.

The reason the numbers range so widely is that “SEO” is not one job. A technical tidy-up, a content programme, a local visibility push and ongoing AI-search work are different pieces of work with different inputs and different measures. Quoting one number for all of them is like asking what “building work” costs.

The main price bands, and what they buy

UK pricing broadly falls into four bands. The figure matters less than what is inside it.

A few hundred pounds, once

A one-off audit or setup: a technical review, a keyword list, some title tags and a report. Useful as a health check. It does not include the work of acting on the findings, so the ranking effect is limited unless you implement them yourself.

A few hundred pounds a month

Usually a light ongoing service: reporting, a handful of content pieces, some link outreach. At this level the work is often templated across many clients, and the difference between it and the band above is mainly the retainer instead of the deliverable.

£1,000–£3,000 a month

A genuine programme: strategy against a defined set of terms, content built to a plan, technical work, and reporting against targets. This is the band where a specialist agency can be good value, provided the scope is specific and the measure is agreed up front.

£3,000+ a month

Competitive, high-volume sectors where the work has to outpace funded rivals: large content operations, digital PR, and constant technical iteration. For most small businesses this is more than the market returns.

Why quotes vary so much for the same brief

When two agencies quote very different figures for what sounds like the same job, the difference is usually one of these:

  • What counts as “content” — a page written and published, or a strategy, a brief and an edit?
  • Whether technical work is included, or quoted separately when the audit finds problems.
  • Whether the price is for the work or for access to a team and a dashboard.
  • Whether results are committed to, or the retainer is for effort rather than outcome.
  • Whether the target terms are chosen for winnability or for impressiveness. A term with 6,000 searches and difficulty 42 is not a small business’s term; it is a line in a proposal.

This is why a scope written first makes the quotes comparable. Three agencies pricing “SEO” are quoting three different products. Three agencies pricing the same defined set of pages and terms are finally quoting the same thing.

What “good SEO” is actually made of

Strip away the packaging and a serious engagement contains some combination of the following. Ask any quote which of these it includes:

  1. Research into what your market searches for, and who currently owns those terms. Without this, everything after it is guesswork.
  2. A page plan: which pages, targeting which terms, in which shapes. The unit of work is the page, not the hour.
  3. Content written to answer real questions, not to fill a blog. This is what earns both rankings and AI citations.
  4. Technical work: speed, structure, structured data, the things machines read. Especially important for AI surfaces, which read text literally.
  5. Migration care whenever URLs change. Where most “SEO” damage happens, quietly, during a redesign.
  6. Measurement against a baseline you took before starting. If there is no baseline, there is no before-and-after, only a report.

A price that includes all six is a different product from one that includes the first two, even if the invoice says “SEO” in both cases.

How AI search changes the scope

The newest line item is visibility in AI answers. It is not a separate discipline from the list above; it is a set of additional requirements on top of it. The same research, the same page plan and the same technical foundations, plus the legibility and corroboration that make a business citable.1 A provider that treats it as brand-new work, rather than as the quality bar SEO is moving toward, is usually pricing a label.

Where it genuinely changes cost: measurement is additional (a question set across several assistants), and the off-site work of being mentioned in the sources assistants trust is slower and less automatable than a blog schedule. Those are real costs, and they should be visible in the scope, not bundled into the word “ongoing”.

How to compare quotes

A short list of questions that turns a vague quote into a comparable one:

  • Which terms and which pages are you targeting, and what is the difficulty of each?
  • What exactly do I receive each month, as deliverables?
  • What is the baseline, and when was it taken?
  • Who owns the content, the accounts and the data?
  • How will you show progress against the target terms and, if relevant, AI citations?
  • What happens at the end — what do I keep, and does the work continue without you?

The last question matters more than most. If the answer is “you lose the access and the reporting”, you are renting the results rather than owning them. That is the same ownership question that runs through website platforms, and it is just as relevant to the marketing attached to them.

A fair budget for a small business

For a UK small business with a modest number of target terms, the honest answer is that SEO is not a monthly mystery bill. It is a piece of research, a set of pages built to it, and then a decision about how much ongoing work the market justifies. The research and the build can be scoped as fixed pieces. The ongoing part is where a budget buys the same again each month — or does not.

At KOODOS that is the ladder: GroundWork (the research, £250, one Demand Map), Build (the pages built against it), and Coverage (the ongoing AI SEO work). The point of doing it in that order is that you only ever pay for the next piece once the last one has shown you what is worth doing. The mechanism behind the third stage is in the main guide: how AI assistants choose which businesses to recommend.

  1. KOODOS AI-visibility baseline, 17 September 2026: 15 questions × Perplexity, ChatGPT, Gemini and Google AI Mode, 60 completed calls. Raw data in docs/research/ai-visibility-2026-09/. ↩