Working out how much to actually spend on SEO is one of those decisions that seems simple until you’re the one accountable for it. Set the budget too low and you’re paying for activity without enough weight behind it to move anything meaningful.
Set it too high without the right structure and you’re funding a wish list rather than a strategy. I want to give you the actual numbers I’d use if I were building this budget myself, not a vague percentage pulled from nowhere.
I’m Myles, Director at Essheo. I’ve managed marketing budgets that included PPC spend alongside SEO for a business that scaled past £65 million in turnover, so I understand the pressure of defending every pound against a finance team asking hard questions. Here’s how I’d actually plan this.
How Much of Your Revenue Should Go Toward Your E-Commerce SEO?
Before splitting a budget into categories, you need a top line figure, and that figure should be anchored to your revenue rather than plucked from an arbitrary number that felt right in a meeting.
The General Rule of Thumb
A reasonable starting point is allocating 5 to 10% of gross revenue to total marketing, with 25 to 50% of that marketing budget going specifically to e-commerce SEO . Where you sit within that range depends heavily on your growth stage, a business trying to establish itself in a competitive category typically needs to sit toward the higher end, whilst an established brand with strong existing rankings can often sustain results with a smaller proportional spend.
How This Breaks Down by Company Size
For businesses under £500,000 in annual revenue, that typically means 8 to 10% of revenue going to marketing overall, with 30 to 40% of that allocated to SEO, translating to roughly £100 to £400 a month at the lower end. Businesses between £500,000 and £2 million typically spend 7 to 9% of revenue on marketing with 25 to 35% toward SEO, in the region of £400 to £1,500 monthly.
Businesses between £2 million and £10 million usually see monthly SEO budgets between £1,500 and £5,000, whilst businesses between £10 million and £50 million typically invest £5,000 to £15,000 a month.
What Should a Monthly SEO Retainer Actually Cover?
Once you know your rough monthly figure, the next question is what that money is actually buying, and this is where a lot of budgets get misallocated without anyone quite noticing until months later.
Typical Cost Breakdown by Activity
A realistic breakdown for e-commerce specifically shows technical SEO audits and fixes costing £2,000 to £8,000 with results typically visible within two to four months, content production for category pages and blog content running £3,000 to £12,000 with a four to eight month ROI timeline, and link building or digital PR costing £2,000 to £10,000 with returns typically taking six to twelve months to show fully.
Product schema and feed optimisation is comparatively inexpensive at £1,000 to £4,000, but delivers results faster, often within one to three months, making it one of the better value additions to any budget.
Full-Service Agency Pricing in Context
A full service e-commerce SEO agency engagement typically runs £5,000 to £25,000 a month, with the wide range reflecting catalogue size, competitiveness of the category, and how much technical remediation is needed at the outset.
For context, the typical annual SEO campaign costs around £120,000 in combined agency fees and internal team time when run at a genuinely serious level, though most growing e-commerce brands operate well below that figure with a properly scoped, more targeted retainer.
How Should You Split Budget Across Different SEO Activities?
This is where the real planning happens, because the same total budget spent in different proportions can produce meaningfully different outcomes depending on your starting point.
A Sensible Default Allocation
A commonly recommended split allocates 40 to 50% of budget to content production and optimisation, 20 to 25% to technical SEO, 15 to 20% to link building, and the remainder to tools and reporting infrastructure.
Smaller businesses under £2 million in revenue often shift this slightly, putting more weight into content given how much category page opportunity typically sits unaddressed at that stage.
Why Category Pages Deserve More Budget Than They Usually Get
Category pages drive 60 to 70% of organic traffic for most e-commerce stores, yet consistently receive the least optimisation attention and budget relative to that impact.
Fixing crawl health before investing heavily in content matters too, stores with unresolved indexation issues show an organic traffic ceiling that content investment alone simply cannot break through, no matter how much is spent on it.
If your budget is heavily weighted toward blog content whilst your core commercial pages remain thin, that allocation needs revisiting before adding more spend on top of it.
Reserving Budget for Testing and Emerging Opportunities
A sensible budget also reserves 10 to 20% for experimentation and emerging tactics, keeping some flexibility to respond to changes in search behaviour rather than committing every pound to a fixed plan set at the start of the year.
Quarterly budget reviews, tracking ROI per activity type, and maintaining this flexibility are what separate a budget that adapts intelligently from one that becomes outdated within six months of being set.
How Should AI Search Change Your Budget Split in 2026?
This is the newest and most important shift in how e-commerce SEO budgets should be structured, and it’s one a lot of existing budget plans haven’t caught up to yet.
Splitting Spend Between Traditional SEO and AI Visibility
A workable default for most businesses in 2026 is keeping the majority of spend in traditional SEO, where it still drives measurable, reliable traffic, whilst deliberately carving out 20 to 40% specifically for AI search and generative engine optimisation, raising that share further as your category’s buyers move more of their research into AI tools.
A strong overall structure allocates roughly 40 to 50% to foundational technical and maintenance work, 30 to 40% to revenue focused growth assets like content and category optimisation, and 10 to 20% specifically to AI visibility initiatives.
Why This Split Matters More Each Quarter
Purchase decisions are increasingly forming before a shopper ever clicks through to a website, shaped by AI Overviews, ChatGPT, and similar tools summarising and comparing products directly, which means budget structured purely around click based traffic is measuring only part of the picture.
This is precisely why we don’t treat AI visibility as a separate line item competing for scraps of an existing SEO budget at Essheo, it’s built into every client roadmap from the outset through what is called Search Everywhere Optimisation, covering Google, AI platforms, YouTube, and the forums that large language models cite from.
What Return Should You Expect on This Investment?
Budget planning only makes sense alongside a realistic expectation of what comes back, and this is where a properly built plan earns its place against other channels competing for the same money.
The Multi-Year ROI Curve
E-commerce SEO produces an average ROI of 0.8x within the first six months, climbing to 2.6x at twelve months, 3.8x at eighteen months, 4.6x at twenty four months, and 5.2x over thirty six months or more, as content and authority compound and content saturation is gradually approached.
Broader analysis across industries puts average SEO ROI as high as 748%, roughly £7.48 returned for every £1 invested, though e-commerce specifically tends to sit at the more conservative end of that range due to typically lower per transaction values compared to service based industries.
Why Cost Per Lead Comparisons Favour SEO
SEO typically delivers a cost per lead around £31, compared to roughly £198 for paid channels, and SEO leads close at a rate of around 14.6%, a meaningfully higher figure than most paid acquisition channels achieve.
For most UK SMEs working with an agency, total SEO investment typically sits between £2,000 and £4,000 a month, a figure worth benchmarking your own plan against if you’re unsure whether your proposed budget is realistic for genuine results.
Ready to Build a Budget That Actually Reflects Your Growth Stage?
We build budget plans at Essheo that are grounded in your actual revenue, category competitiveness, and growth stage, not a generic percentage pulled from an industry average with no context attached. Our clients have generated over £45 million in combined revenue over the last two years, and every senior practitioner on our team brings 8+ years of experience each, ranking against genuinely tough competition including household names like MoneySuperMarket, GoCompare, and uSwitch.
If you’re a marketing manager, business owner, or stakeholder trying to work out exactly how much to budget for SEO next year and where that money should actually go, I’d rather build that plan with you properly than leave you guessing from a generic percentage.
Book a strategy call with me and I’ll map out a realistic, revenue anchored SEO budget for your specific business.