Published 2026-09-05 · Last updated 2026-09-05
ChatGPT does not keep its own map of every plumber in your town. When someone asks it for a plumber, it rewrites the question into one or more search queries, sends them to an outside search provider, reads the pages that come back, and adds licensed data such as Yelp reviews before it writes an answer. The plumbers it names are the ones that show up in that search index, allow OpenAI's crawler, and carry reviews the assistant can cite.
Where does ChatGPT get its search results?
OpenAI said it plainly when it launched ChatGPT search in October 2024: the feature uses third-party search providers as well as content provided directly by partners, and any website can choose to appear in ChatGPT search through its crawler controls.
The OpenAI Help Center, updated in August 2026, describes the mechanism. ChatGPT search sometimes partners with other search providers, and when it does, it typically rewrites your question into one or more targeted queries that it sends to those providers. So 'who is a good plumber near me' becomes a handful of searches, and the answer is built from what those searches return.
Why does Bing matter if nobody you know uses it?
Because Microsoft names ChatGPT as one of the products Bing feeds. In a June 2025 Bing Webmaster Blog post, Microsoft wrote that Bing powers a wide range of AI and search experiences, including Yahoo, DuckDuckGo, Microsoft Start, and AI tools like ChatGPT and Inflection.ai.
Microsoft's own assistant is built the same way. When Microsoft introduced the new Bing in February 2023 as your copilot for the web, it said the product ran on an OpenAI model customized for search. Copilot is Bing plus an OpenAI model. ChatGPT search is an OpenAI model plus outside search results. Either way, the index your site sits in is the one that gets read.
So a plumber who has never looked at Bing can still be missing from ChatGPT because the site was never indexed there, or was indexed with a wrong phone number and an old address.
Can ChatGPT read your website at all?
Only if you let it. OpenAI's crawler for search is called OAI-SearchBot, and OpenAI's developer documentation states that sites opted out of OAI-SearchBot will not be shown in ChatGPT search answers. GPTBot, the crawler used for training, is a separate toggle. Changes to a site's robots.txt file take about 24 hours to apply.
This is where a lot of well-meaning blocks backfire. Some site owners, or the agencies who built their sites, blocked every AI crawler in one line to keep their content out of training data. That same line can keep the business out of the answer when a customer asks for a plumber. Blocking GPTBot and allowing OAI-SearchBot are two different decisions, and you can make them separately.
What role do Yelp reviews play?
A large one. Foundation Marketing and AirOps studied more than 28 million AI responses to local business questions between September and November 2025, across ChatGPT, Gemini, Perplexity, and Google AI Mode. Yelp earned 512,680 citations, 3.4 times the next local platform, and took 72.5% of competitive local citations on Google AI Mode.
The plumbing numbers in that study are specific. Twenty-four different 'plumber near me' prompts on Perplexity produced 1,168 answers that cited Yelp. Home services 'near me' answers overall cited Yelp more than 66,000 times in the quarter. And since the deal that became public in July 2026, ChatGPT holds a direct license to show Yelp reviews, ratings, and photos in its local answers.
The assistant is doing what a careful homeowner does: reading reviews before it names anyone. A plumber with a thin or stale Yelp page is giving it less to work with.
The four doors, and who holds the key
| Door | What it controls | What you can do |
|---|---|---|
| Bing's index | Whether ChatGPT and Copilot can find your pages | Verify the site in Bing Webmaster Tools and submit your pages |
| OAI-SearchBot access | Whether ChatGPT is allowed to show your site | Check robots.txt; allow OAI-SearchBot even if you block GPTBot |
| Your Yelp page | The reviews, rating, and photos the answer can cite | Keep category, hours, and phone current; ask for reviews |
| Your own pages | The facts the assistant reads once it finds you | One clear page per service, with service area and phone |
None of these four is expensive. Two of them, the crawler setting and the Bing verification, take an afternoon. The other two are habits: keeping a listing current and asking for reviews after good jobs.
How many customers are asking ChatGPT?
The Pew Research Center surveyed 5,119 US adults in February 2026: 44% use ChatGPT, about 40% use a chatbot to find information, about half use AI chatbots at all, and one in four use one daily. That is not a niche. It is a share of the same people who used to type your trade into Google.
None of this means a plumber should abandon Google. It means the pipeline has more than one intake, and the cheapest fixes are the ones in the table above: open the crawler, get into Bing, and keep the review page alive.
Common questions
Does ChatGPT use Google's results?
OpenAI says it uses third-party search providers and does not name them in its help pages. Microsoft names ChatGPT among the AI tools Bing powers in its June 2025 webmaster post. Plan around Bing.
If I block AI crawlers, am I invisible in ChatGPT?
If you block OAI-SearchBot, OpenAI's documentation says your site will not be shown in ChatGPT search answers. Blocking GPTBot alone does not have that effect; it is a separate toggle.
How fast does a robots.txt change take effect?
About 24 hours, according to OpenAI's developer documentation as of September 2026.
