AI Search Marketing Budget: Where AEO and GEO Spend Is Going

Look at where the share moves first. In the ThriveStack citedby model, AI search gains 8.8 points of the marketing mix between 2025 and 2027. Every other large channel gives up a little to pay for it. The model is a simple projection of direction. It does not measure real spend.

Brand and sponsorships slip 2.8 points. Paid search slips 2.6 points, from 15.4% to 12.8%. Those are slow slides over two years. Influencer and events hold steady.

So should you cut paid search? Only after you can see what AI search returns. Paid search still buys demand you can count today, and AI search spend is harder to count. Start with the budget line you can least tie to revenue, and fund the test from there.

The table shows the full projection, year by year. Each year is rescaled to 100% so the shares add up. It is the ThriveStack citedby model, and it is not survey data.

AI search (AEO and GEO) climbs from 4.6% of the marketing mix in 2025 to 13.4% in 2027. That is 2.9 times the share. The year-by-year columns show the gain is steady: about 4 to 5 points a year.

Read the model next to the surveys. Conductor's 12% is a share of enterprise digital budgets, while the model's 4.6% is a share of the whole mix. The bases differ. Use the model for the trend and the surveys for the size.

Barely. Gartner's 2026 CMO Spend Survey puts marketing budgets at 7.8% of company revenue in 2026, up from 7.7% in 2025. It surveyed 401 CMOs and marketing leaders in North America, the UK and Europe between January and March 2026. Gartner calls budgets "effectively flat".

The pie is not getting bigger, and the squeeze is real. 56% of those CMOs say they lack the budget for their 2026 strategy.

Gartner's AI-ready organizations spend more, at 8.9% of revenue. They are the exception. For most teams, every new dollar for AI search has to come from another line.

Two 2026 surveys measure it, and each measures something different. Gartner finds CMOs put an average 15.3% of marketing budgets into AI initiatives. That covers all AI, from content tools to analytics. AI-ready organizations put in 21.3% (Gartner).

Conductor asked more than 250 senior enterprise executives about AEO and GEO alone. They put an average 12% of digital marketing budgets there in 2025, and 94% plan to raise it in 2026 (January 13, 2026).

Do not add these numbers together. The bases differ: all AI against AEO and GEO, total budget against digital budget. Read them side by side and the message is plain. AI search already holds a real slice, and the slice is growing.

One caution. 97% of those executives said AEO and GEO already drives a positive business impact. That is a self-report in a vendor survey. Treat it as sentiment, then measure your own.

Because the visits are the small part. Conductor's benchmarks found AI referrals make up 1.08% of website visits. The study covered 13,770 domains, 10 industries and more than 3.3 billion sessions (updated July 6, 2026). Yet enterprises put 12% of digital budgets into AEO and GEO.

Do not read the two numbers as a ratio, because different datasets produce them. They do point at a measurement problem. Most AI influence leaves no visit. A buyer reads an answer, then searches your brand. Similarweb found that 56% of AI-influenced visits arrive through branded search, against 40% of standard visits (June 23, 2026).

That is why the spend is easy to start and hard to defend. Your analytics show 1%. Your buyers show more. Our guide to GA4 AI traffic shows what analytics can see, and our guide to AI search revenue attribution shows how to tie it to closed revenue.

This is the real worry. A CFO asks what the AI search budget returned, and the honest answer today is "it depends on who you ask". The published studies do not agree.

Ahrefs found AI visitors converted 23 times better than organic visitors on its own site (June 16, 2025). Semrush modeled 500 topics and put an AI visit at 4.4 times the value of an organic visit (July 21, 2025). Amsive studied 54 sites and found 4.87% for AI traffic against 4.60% for organic, a gap with no statistical significance (September 3, 2025).

So do not borrow a number. Work out your own. Take closed-won revenue from AI-sourced visits and subtract what you spent on AI visibility. Divide by that spend. Give each cohort a full sales cycle before you judge it.

No trusted split exists yet. Some guides give a range of 10% to 50% of the SEO budget. Similarweb's budget guide (January 12, 2026) attributes a range like that to Conductor's benchmarks. We could not find it in Conductor's published report, so treat it as one opinion.

Use gates instead of a percentage. Spend a small test amount first. Raise it as the evidence arrives.

Gartner's data backs this order. AI-ready organizations spend more on AI and more overall, and they built readiness first. Only 30% of CMOs report mature AI readiness, and 70% say their processes are not yet ready to scale AI (Gartner).

The gates map to the four steps in ThriveStack citedby: audit your AI visibility, fix the gaps, track citations, and attribute them to revenue.

Budgets are flat, AI search is taking a larger slice, and the visits are small. So the next 90 days are about evidence. Work in three blocks.

Days 1 to 30. List your budget by channel. Audit your AI visibility. Count AI visits and bot fetches.

Days 31 to 60. Ring-fence a test budget. Fix the pages AI cites. Track citations by engine.

Days 61 to 90. Join sessions to your CRM and billing data. Report revenue by AI source. Reset next year's mix with what you learned.

Read our AI visibility playbook for the content work, and our AI visibility metrics guide for what to report. Our cross-channel attribution guide covers the join.