People everywhere are increasingly turning to AI for information, with popular search tools like ChatGPT boasting over 800 million weekly active users. But should they rely on it for serious topics such as mortgages and homebuying?
New research from Barratt Homes reveals that almost a quarter (24%) of Brits have used AI tools for mortgage advice. In partnership with Barratt Homes, Terry Higgins, Group MD at TNHG Mortgage Services, warns consumers to take caution when turning to AI for financial decisions, as research reveals different models may even make different financial recommendations based on the same prompt.
Higgins says:
“AI search tools can be helpful for making mortgage jargon and other information more accessible to first-time buyers and homeowners. However, users should be careful when using them, especially for financial decisions, as outputs aren’t always accurate and could be biased. A qualified mortgage adviser will look at your full financial picture and will match you with lenders and products that suit your circumstances. They can also explain the full costs involved and guide you through each step of the purchase, which is something AI simply can’t do.”
More than one in 10 Brits use AI to see how much they can borrow
Survey respondents reported using AI for a range of mortgage-related tasks, including:
- Understanding mortgage jargon (16%)
- Checking how much they can borrow (12%)
- General homebuying advice (12%)
- Understanding interest rates (11%)
- Comparing mortgage deals (10%)
Terry Higgins comments:
“Calculating affordability is one of the most complex parts of buying a house, and there are so many factors at play. While AI can be a good starting point, it’s been known to make mistakes with basic calculations and even hallucinate or invent fake data and numbers. The same applies for things like interest rates – AI can provide a helpful breakdown, but it can’t be trusted to give you accurate, real-time information.
An experienced adviser will assess your income, outgoings and credit profile in detail, access a wide range of lenders, and provide a realistic borrowing figure based on current criteria – not assumptions. They’ll also help you understand how changes in rates or circumstances could affect your options.”
Different AI tools give different mortgage answers – expert urges caution
The research asked a range of popular tools including Copilot, ChatGPT, and Grok to assess a typical first‑time buyer’s affordability and whether a two‑ or five‑year fixed rate might be better. Despite using identical information, each AI tool gave different answers – including different affordability expectations and different recommendations on the best mortgage term.
|
Model |
Affordability stance |
Fixed-rate view |
Guidance style |
|
Copilot |
The most neutral, saying the purchase “lined up well with typical UK lending patterns” without leaning optimistic or cautious. |
Offered a balanced comparison of two‑ vs five‑year fixes, framing the choice around lifestyle, budgeting, and risk comfort. |
Practical, simple, consumer‑friendly. Focused on actionable steps like getting a Decision in Principle. |
|
ChatGPT |
The most cautious, describing the £230k target as “borderline but plausible,” depending on lender strictness and affordability checks. |
Leaned toward a five‑year fix, highlighting stability for first‑time buyers and the risk of future rate rises. |
Detailed, structured, broker‑like. Used step‑by‑step breakdowns and multiple caveats. |
|
Grok |
The most optimistic, describing the scenario as “promising and affordable,” mentions lenders offering 5x and above income multiples. |
Favoured a two‑year fix, citing 2026 forecasts, expected rate drops, and competitive short‑term pricing.
|
Analytical and data‑heavy, heavily referencing market conditions and interest‑rate movements. |
With different models producing such different outcomes, Higgins warns consumers:
“Mortgage decisions depend heavily on personal circumstances like income, debt and spending – and much of that is sensitive financial information. With AI tools giving inconsistent answers, consumers can’t get a truly accurate picture of their affordability without sharing data they may not feel comfortable putting online. A mortgage advisor can handle this information securely.
“AI may also miss certain options like deposit‑boosting schemes or equity loans, meaning buyers could miss out on savings that a qualified advisor would highlight. Indeed, buying a new home opens a range of mortgages which aren’t always available to consumers going direct to the lender.
“With interest rates changing regularly, it’s best to use AI as a guide, not a replacement for expert advice. Speaking to a professional mortgage advisor is still the safest way to get accurate, up-to-date information. A good mortgage advisor doesn’t just help you find the right products; they have relationships with the lenders and are there for the full application process, helping to avoid delays, keeping your purchase on track. They will act as a single point between you, the lender and your housebuilder.”
The dos and don’ts of using AI for mortgage guidance
Higgins says: “AI may never provide 100% accurate information, but as it becomes an everyday tool for many people, there are some steps you can take to get a better response, as well as protect yourself.”
Do: Be specific with your prompt
Provide as much non‑sensitive context as possible so the AI can tailor information more accurately (for example: “first‑time buyer,” “10% deposit,” “interest‑only vs. repayment”).
Don’t: Use sensitive personal information
Avoid including details such as your full income, employer, bank details, National Insurance number, credit score, or personal identifiers. These aren’t necessary for AI to give general guidance and could create security risks.
Do: Treat AI as a starting point, not a final answer
Use AI to help you understand terminology, compare general mortgage types, or explore what questions to ask a broker. It’s a good tool for building confidence before speaking to a professional; not a replacement.
Don’t: Ask for direct recommendations
AI cannot account for your full financial picture and may offer incomplete or incorrect advice on products, lenders, or mortgage terms. It should never replace a qualified mortgage advisor. It’s better to use AI for general guidance rather than affordability information, lending criteria, and other points that can change quite often.
