Short answer: UK SEO agencies commonly charge £1,000-£5,000+ a month depending on scope and company size, with an account manager between you and the technical work. A consultant typically costs less for comparable scope and gives direct access to the person actually doing the SEO — the real trade-off is bandwidth (an agency team) versus access (one senior person's full attention).

1. What UK SEO agencies typically charge

Small business retainers often start around £750-£1,500/month for a limited scope (on-page + basic technical fixes), scaling to £3,000-£5,000+/month for competitive industries or larger sites needing ongoing content and link-building programs. Enterprise SEO programs with dedicated teams can run well beyond that. The account structure matters as much as the number: many agency retainers include a mix of senior strategy time and junior execution time, billed at a blended rate.

2. What a consultant retainer looks like instead

A UK SEO consultant retainer for comparable scope commonly runs lower than an equivalent agency package, because there's no account-management layer or junior execution team billed into the price — you're paying for one senior person's direct time, not a team's blended rate. The trade-off is bandwidth: a consultant can't match an agency's capacity for large-scale content production or link-building campaigns running in parallel across many pages at once.

3. When each format actually makes sense

Early-stage and small UK businesses are usually better served by a consultant — a single senior person auditing and fixing the technical foundation, then building an intent-mapped content strategy, covers most of what a small site needs. Larger UK businesses with big content libraries, multiple product lines, or aggressive link-building targets often need agency-level bandwidth on top of a consultant's strategic oversight, not instead of it.

4. Questions worth asking before signing either

  • Will a technical SEO audit happen before any retainer is quoted, or is the price fixed regardless of what's actually wrong?
  • Who does the strategy work, and who does the execution — are they the same person?
  • What's the reporting cadence, and does it tie back to organic traffic and leads, not just rankings for vanity keywords?
  • What's the notice period to cancel or scale down?

The honest answer to "agency or consultant" is usually "it depends on how much execution bandwidth you actually need" — not which one is objectively better. Match the format to the size of the problem, not the size of the invoice you're used to seeing.