How to Budget for AI Search in 2027: 10%, and Which Line Pays for It

How much should you spend on AI search in 2027?

Put 10% of your total marketing budget against AI search in 2027, and find it inside the budget you already have. If you spend £60,000 a month, that is £6,000. Under £20,000 a month, don't create a separate line at all: fold the work into SEO and PR and spend nothing extra.

I'm writing this as an owner, not a marketer. I run SugarNova Group, and I built it by buying and running businesses, so I read a marketing budget the way I read a P&L. Every line has to show what it bought, and a new line has to say which old one it replaces.

So treat the 10% as my recommendation, not a law. I haven't seen a study that ties a share of budget to a lift in AI citations, and anyone quoting you one is guessing. What the number does is force the question most 2027 plans skip: which existing line pays for it?

Carrie Rose, founder of Rise at Seven, published a strong guide to GEO budgets on 23 October 2026. She recommends at least 8 to 10% for large and enterprise brands, reallocated from every discipline rather than taken from SEO alone. I agree with the principle. Her worked examples start at a £500,000 PR budget, though, so I've worked this one at the scale most operators actually run: £10,000 to £250,000 a month in total.

Are UK marketing budgets flat going into 2027?

No. UK marketing budgets rose at their fastest rate in more than two years in the third quarter of 2026, according to the IPA Bellwether Report for Q3 2026, as reported by InPublishing on 21 October 2026. A quarter of firms (25.6%) raised budgets and 11.3% cut them, a net balance of +14.3%.

The flat reading comes from the remaining 63% or so who left budgets unchanged. Both statements are true. Only one is the headline.

Public relations led every category in the same report, at a series-high net balance of +15.3% and a 13th straight quarter of upward revisions. The outlook is tighter: the report cut its adspend growth forecast for 2027 from 2.3% to 1.3%.

My read is that the window is this quarter. Budgets have room now, PR is where UK money is already moving, and new lines will be harder to win once 2027 starts. Set the AI search line before January, not in March.

I learned that one the hard way. In 2020, COVID closed every restaurant client we had and we had to move the business into paid media and lead generation. Set your lines while you have room, because a bad quarter makes the choices for you.

Should the AI search budget come from SEO, PR or paid?

Take most of it from PR and paid, not SEO. AI assistants build their answers mostly from what other people publish about you, so the work that moves those answers looks more like PR than classic SEO.

Muck Rack's What Is AI Reading? report (May 2026) analysed more than 25 million links cited by ChatGPT, Claude and Gemini. About 84% came from earned media: journalism, research, reference sites, social platforms and third-party content. Paid and advertorial content accounted for 0.3%.

The October 2026 edition, as summarised by Unite.AI on 28 October, found earned sources still at roughly 84%. Journalism's share fell from 27% to 22%, and brands' own content rose from 13.7% to 15.2%.

Here is what I take from that. PR is the biggest lever, because earned sources dominate. Your own pages matter more every quarter, so SEO keeps its funding. And paid ads are almost never cited, which makes paid the right place to take money from, as long as you take it from the weakest part of the account.

One caution, which Carrie Rose makes too: never copy citation shares straight into budget lines. A source being cited doesn't prove it caused the recommendation, and share of citations isn't return on spend.

What does the money buy at £20k, £60k and £150k a month?

At every level the order is the same: fix your own pages, then earn mentions in the sources AI engines already cite, then amplify what works. The splits below are my recommendation for a brand selling direct or generating high-value leads. They are not an industry benchmark.

Take the paid share from spend that buys sales you'd have made anyway: branded search you already rank first for, and retargeting to people already in the basket. Platform-reported return flatters exactly that spend, as our guide to ROAS explains. Read the P&L as an owner and it's the first line you'd question.

Protect the SEO that already earns revenue. AI search runs on pages that can be crawled and understood, and the six shifts in our 2027 briefing all start from that foundation.

How do you know whether AI search spend is working?

Use a fixed set of buyer questions, asked the same way every month. One AI answer tells you almost nothing, because answers vary between engines, between days and between identical prompts.

1. Write down 20 questions your buyers ask before they buy, in their words, not yours.
2. Ask each one in ChatGPT, Gemini, Perplexity and Google AI Mode once a month, logged out, with identical wording. That is 80 answers.
3. For each answer, record whether you are named, which competitors are named and which sources are cited.
4. List the cited sources. Those pages are the pool you need to be in, and they become your PR target list.
5. Add one question to your enquiry form: how did you hear about us, with an AI assistant as an option.

Track three numbers: the share of the 80 answers that name you, the share of cited sources that mention you, and enquiries that mention an AI assistant. Watch branded search volume alongside them, because someone who meets you in an AI answer may well search your name rather than click a link. There is more on how we approach this on our GEO page.

Attribution here is weak, and my prediction is that it stays weak through 2027. Judge the line at 90 days, against the 80-answer baseline you took before spending anything.

What should you do first?

Run the 80-answer check before you move a pound. Everything after it depends on knowing where you stand.

1. Take the baseline: 20 questions, four engines, logged out.
2. Fix your own pages: a direct answer near the top of each commercial page, schema, and the same company facts on your site, your Google Business Profile and the directories you control.
3. Map the cited sources and get onto the ones you can: directories, roundups and review sites first, then the publications PR can reach.
4. Move the money before January, from the lines in the table above.
5. Review at 90 days, not 30.

If you're planning 2027 now and want the baseline taken for you, book a free growth audit. We'll show you what AI assistants say about your brand today and where the first £1,000 of the line should go.