What affects website design costs? The 6 factors UK agencies calculate
The six factors UK agencies calculate to quote your website design. Page complexity, design tier, content, integrations, CMS, and migration baggage — and how each moves the price up or down.
By James Sheen
What affects website design costs? The 6 factors UK agencies calculate
Six things drive your website design cost: the number and complexity of page templates, whether you need custom design or theme customisation, who writes your copy, which third-party tools need connecting, whether you need a CMS, and how much migration baggage you carry from your current site. Every quote you receive is some combination of these six. For the full UK price bands across project types, the pillar guide covers those in detail.
At a glance: the 6 factors
| Factor | Moves price up | Moves price down |
|---|---|---|
| Pages and complexity | Many bespoke templates | Templated or minimal pages |
| Design tier | Greenfield custom design | Shopify or WP theme customisation |
| Content and copy | Agency-written copy per page | Client provides final copy |
| Integrations | CRM, bookings, payments | Basic contact form only |
| CMS | Full CMS with content modelling | Static site or platform native |
| Migration | Redirect mapping, content port, SEO preservation | Greenfield build, no history |
These factors compound. A project with bespoke design, agency-written copy, three integrations, and a content migration is not six times more expensive than a simple brochure, but it is considerably more than any one factor alone would suggest.
1. Pages and page complexity
The first question in every website design cost conversation should be: "How many page templates, and at what complexity?" Not pages, templates. One template can power many pages, but each template still has to be designed and built from scratch. In practice, most SMB sites need fewer templates than they expect.
Templates fall into rough tiers. Bespoke templates (homepage, key landing pages) involve original design and full-custom build. Structured templates (services, about) follow a layout pattern but still need design attention. Templated patterns (location pages, FAQs) reuse an existing structure with swapped content. Minimal pages (legal, T&Cs) are largely text and rarely need their own template.
DotGO puts the average 5-page brochure at around £720, which sits firmly in the templated tier. Add a bespoke homepage design and a custom services layout, and that number rises quickly. A 5-template site at bespoke complexity is roughly twice the work of a 5-template site where everything is templated.
More detail on templates vs pages in Section 2 of the pillar.
2. Custom design vs theme customisation
If you're building on an existing platform (Shopify being the most common one I work with), the design lives within the platform's structure. That is not a limitation. For most UK SMBs it is the sensible call: faster, lower floor cost, and the ceiling is higher than most projects actually need.
Greenfield custom design means starting from nothing: brand discovery, layout exploration, full creative direction before a line of code gets written. It is the right approach when your brand genuinely needs a look no template can deliver. It also costs more, because you are buying the thinking as well as the output.
The honest framing: if a platform theme covers 80% of what you need, customising one is the right call. If your brief requires the other 20% to be unique to you, custom is worth the premium. Yellowball's cost overview and GoDaddy UK both document this fork clearly: agency custom design adds a significant overhead that platform builds do not carry.
3. Content and copy
Who writes the words? This question is underestimated in almost every project I quote.
If you arrive with final copy ready to drop in (a services page you have already written, an about section you are happy with, product descriptions done), the build stays leaner. Copy is costed per page, not per template: every page needs its own words even if the template repeats. A site with 10 content pages needs 10 sets of copy regardless of how many unique template designs it uses.
If you need copy written in a brand voice (a homepage that converts, a services section that answers real objections, an about page that sounds like a person) that is a separate line item, and a real one. Budget roughly £150–£500 per content page for properly written, SEO-considered copy. Most projects underestimate this until the brief is finalised.
4. Integrations
A basic contact form costs nothing extra. Anything beyond that is a separate scope item.
Connecting a booking tool like Calendly to your calendar, routing leads into HubSpot, or setting up payment capture with Stripe: each of those is a small project within the project. They are well-documented, reliable tools, but wiring them into a site still takes build time, testing, and edge-case handling. What does the confirmation email look like? What happens when a booking clashes? What triggers the CRM record?
Each integration adds a flat overhead to the quote. One integration is manageable. Three integrations is a meaningfully larger project than a site with none.
5. CMS choice
Not every site needs a CMS. A brochure site for a sole trader might be updated once a year. A simple platform like Shopify or Squarespace has content editing built in. Adding a full content management system on top is overhead (setup time, schema design, admin configuration, and training) that only pays off if you actually plan to update the site regularly.
When a CMS adds genuine value: content teams publishing blog posts, products changing frequently, a marketing function that needs to control copy without a developer in the loop. When it is overhead: a five-page brochure where the copy will not change for two years.
I factor CMS setup as a fixed overhead per project when it is genuinely needed. On projects where it is not, I leave it out. The question to ask any agency is whether the CMS they are proposing is genuinely required by your workflow, or whether it is a default they add to every project.
6. Migration baggage
Greenfield builds are cheaper to scope because there is no history to manage. Rebuilds are not. The truth is, most clients don't realise this until the quote comes back higher than they expected.
If you are replacing an existing site, you carry obligations into the new build: URLs with organic search equity that need redirect mapping, content that needs porting, and a go-live moment that requires careful handover to avoid ranking drops. GoDaddy UK and Authentic Style both flag migration as a consistent cost driver on UK rebuild projects.
A redirect map on a 50-page site is a straightforward task. A redirect map on a 400-page site with a complicated URL structure is a project of its own. Add content migration, image exports, and a staged go-live, and the overhead ranges from around £500 to £2,000 depending on volume and complexity.
A rebuild done badly costs more than the rebuild itself. You can undo years of organic traffic in an afternoon if the redirect map is wrong.
How agencies actually calculate
Most UK web agencies (including me) run a formula that combines a design overhead, a build overhead, and per-template rates at the complexity levels above. The six factors feed into that formula: complexity tier drives the per-template rate; integrations and CMS add flat overheads; copy adds a per-page line; migration adds a scope block. The quote is the sum.
What this means practically: when you ask for a website price before you have answered the six questions above, you will get a wide range. When you can answer them, you will get a sharper number. If you want to understand how to brief a project so that quotes land closer together and fairer to you, the briefing guide for UK small businesses covers that in full.
For full cost bands across UK project types, the complete pricing guide is worth the read before you start getting quotes.
References
- GoDaddy (2026). How Much Does a UK Website Cost? https://www.godaddy.com/resources/uk/smallbusiness/how-much-does-it-cost-to-build-a-website-uk
- Yellowball (2026). How much does a website cost in the UK? https://weareyellowball.com/guides/how-much-does-a-website-cost-in-the-uk/
- DotGO (2026). How much does a website cost? https://www.dotgo.uk/lp-web-design/how-much-does-a-website-cost
- Authentic Style (2026). How much does a website cost UK? https://authenticstyle.co.uk/how-much-does-a-website-cost-uk/
- Hollis Web (2026). How much does a website cost in the UK? https://hollisweb.co.uk/how-much-does-a-website-cost-in-the-uk/
