That is the whole answer. The rest of this post is the working.
Why AEO doesn't need extra budget on top of good SEO
AEO doesn't need extra budget on top of good SEO because most of AEO is SEO. That isn't my opinion dressed up as a fact. Google's guide to AI search asks whether SEO is still relevant for generative AI search, and answers:
"In short, yes! The best practices for SEO continue to be relevant because our generative AI features on Google Search are rooted in our core Search ranking and quality systems."
If a page isn't indexed and ranking, it isn't in the pool an answer engine picks from. So the crawling, the internal links, the content that matches what people search for, the backlinks: you are already paying for those. Or you should be.
Which brings me to the uncomfortable version of this question. A lot of people asking "do I need extra budget for AEO" don't have an AEO problem. They have an SEO budget that was never big enough to build authority, and a new acronym has just made that visible.
Where extra AEO budget does go
Extra AEO budget, when it is justified, goes to three places.
Measurement. Citations are not clicks, so your current reports can't see them. You can start for nothing with Bing Webmaster Tools, Search Console and Microsoft Clarity. The paid prompt trackers in our tool directory run from $20 a month to several hundred. Then there are the hours for somebody to read the thing, which is the real cost.
Third-party coverage. The engines lean on pages you don't own. In our September 2026 AI Visibility Index, 226 of 358 AI answers about hiring an agency cited a "best of" list. Getting onto pages like that is PR, and PR was never free.
The questions behind the question. Query fan-out means the engine searches a cluster of related questions, not only the one that was typed. Covering those is content work. If you already have a content budget, this is a change of brief. It is not a new line.
Notice what is NOT on that list: a second strategy or a second technical retainer. A new acronym (read: a new invoice) doesn't create new work.
How much extra budget AEO takes if you buy it from an agency
How much extra budget AEO takes when you buy it from an agency depends on what they add to the SEO you already have. So ask for the deliverables as a list, strike out anything that is SEO under another name, and price what is left.
For scale: 87 of the 345 providers eligible for an EliteAEO ranking publish a monthly starting price. The median is $1,500 a month, and the middle half runs from $750 to $2,600. Among providers ranked for SaaS it is $2,250. Those are starting prices for a whole retainer. If the "AEO add-on" on your quote costs more than a whole retainer does elsewhere, ask what is in it.
I do think AEO deserves its own track in the report. Separate numbers, separate targets, reviewed on their own schedule. Mixing rankings and citations into one "is it working?" answer confuses everybody, including the agency. But a separate track in a report is a reporting decision. Whether it becomes a separate invoice should depend on the extra work, and you are entitled to see that work listed.
Who should spend more on AEO, and who shouldn't
Who should spend more on AEO comes down to how much research your buyers do before they contact anyone. The more questions they ask first, the more of those questions now go to an AI engine, and the more it matters whether you are named in the answer. That is where I would move money.
And if your SEO is weak? Don't spend a cent on AEO yet. Fix the foundation. Money spent on answer engines that can't find you is money spent printing brochures nobody will be handed.
The State of the AEO Agency Market 2026 has the price data by industry, and the AEO FAQ covers what AEO costs in more detail.