How to Write a Business Plan With AI in One Afternoon (Free Template and 12 Prompts)

The idea is clear in your head. Then the bank, the landlord or the Start Up Loan form asks for a business plan, and you are looking at a blank page with a heading that says "Executive Summary". Most plans stall there. The ones that get written are often written once, for the lender, and never opened again.

That is a waste, because the plan is the cheapest test your idea will ever get. Office for National Statistics figures show that 93.4% of UK businesses started in 2019 survived their first year, but only 38.4% were still trading after five. A plan will not save a bad idea, but it will show you the hole in the numbers while fixing it is still free. This guide shows how to write a business plan with AI in one afternoon: a template with the ten sections lenders expect, twelve prompts to copy, and the checks that stop an AI making your market up.

How we checked this guide

1. Official guidance first. What a plan should contain comes from GOV.UK, which also links the free templates named below.
2. Loan terms from the source. Start Up Loan figures were read on GOV.UK on 4 October 2026.
3. Survival figures from the ONS. They come from Business Demography 2024, published in November 2025.
4. A method, not magic. An AI can draft and research. It cannot know your prices, your customers or what you can afford to lose. The method below keeps those jobs with you.

The free template: 10 sections every plan needs

GOV.UK describes a business plan as a written document covering your objectives, strategies, sales, marketing and financial forecasts. Laid out as sections, that looks like this:

GOV.UK links two free templates in this shape: one from The King's Trust and one from Start Up Loans, which also offers a cash flow forecast template. Use either as the document you fill in, and use the AI to fill it properly.

The one-afternoon method

Hour 1: let the AI interview you

Do not ask for a business plan. Ask to be interviewed. A plan written from a one-line idea is generic, and lenders have read hundreds of those. A plan written from your own answers sounds like a business.

1. "I am starting a mobile dog grooming business in Leeds. Interview me one question at a time until you can write sections 2, 3 and 6 of a business plan. Ask about my experience, my customers, my prices and my costs."
2. "From my answers, write section 2 in plain English, under 250 words, in the first person."
3. "List the ten assumptions in my answers that I have not proved yet, most dangerous first."

Hour 2: research the market, with sources

This is where an AI saves the most time and where it does the most damage if you trust it blindly. Ask for sources every time, and open them.

4. "Find six competitors within ten miles of Leeds city centre. For each, give services, prices and a link to the page where you found the price. Put it in a table."
5. "Find official figures for the size of this market in the UK. Use only government, trade body or named survey sources, link each one, and tell me if you could not find a figure."
6. "Based on the competitor table, suggest three price points and what each would mean for my margin."

The guide to running deep research with AI shows how to brief a longer research task.

Hour 3: build the numbers

A lender reads the cash flow forecast before the words. It shows, month by month, what comes in, what goes out and whether the bank balance ever drops below zero.

7. "Build a 12-month cash flow forecast as a spreadsheet. Ask me for each cost and for my expected sales per month before you fill anything in. Do not invent a number."
8. "Add three versions: sales as I expect, sales 30% lower, and sales arriving two months late. Show the lowest bank balance in each."
9. "List the costs new businesses in my trade often forget, and ask me whether each applies."

Put your own pay in the forecast. Use real 2026 figures where they apply: the National Living Wage is £12.71 an hour for staff aged 21 and over, and you must register for VAT once taxable turnover passes £90,000 in a rolling 12 months. If spreadsheets are not your strength, our 20 AI Excel tips help.

Hour 4: attack it, then tidy it

10. "Act as a cautious bank lender reading this plan. List every weakness, missing figure and claim you would not believe, in order of seriousness."
11. "Rewrite the summary last. One page, plain English, no adjectives I cannot prove."
12. "Turn the plan into a ten-slide presentation with one message per slide."

Fix what prompt 10 finds before anyone else reads it. Then turn it into slides if you have to present: the guide to making a presentation with AI covers the rest.

Four checks before anyone sees it

AI gets things wrong in ways that look confident. A plan with one invented statistic loses the reader's trust in every other number.

• Open every source. If a figure has no link, or the link does not say what the plan says, delete the figure.
• Recalculate one month by hand. Pick a month in the forecast and add it up yourself. If it is wrong, ask for the formulas and check them.
• Read it aloud. Anything you would not say to a customer does not belong in the plan. Cut "innovative", "passionate" and "unique".
• Ask one real person. A customer, a supplier or someone in the trade will tell you in five minutes what a model cannot.

What a lender wants to see

The government-backed Start Up Loan is the route many new UK businesses take, and its terms tell you what a plan is for. On 4 October 2026 GOV.UK listed them as:

• Amount: £500 to £25,000.
• Interest: a fixed 7.5% a year.
• Term: 1 to 5 years, with no application fee and no fee for repaying early.
• Who: aged 18 or over, with a UK business that has been fully trading for less than 5 years.
• Support: help with the business plan before you apply, and up to 12 months of free mentoring if you are successful.

It is an unsecured personal loan, so you pass a credit check and you owe the money yourself. That is why the forecast matters more than the prose: the question a lender is asking is whether the business can make the repayment in its worst month. Show the version with sales 30% lower and the answer is already on the page.

Nobody asks whether an AI helped you write the plan. They ask whether you can explain every number in it without looking.

How an AI agent helps beyond the draft

ChatGPT, Claude, Gemini, Microsoft Copilot, Manus and Meta's Muse will all draft sections if you paste in your notes. An agent goes further because it produces the files, not just the text.

• Runs the interview and keeps the answers. One conversation holds your notes, the research and every version of the plan.
• Researches with links. Competitor prices and market figures arrive in a table with the page each came from.
• Builds the spreadsheet. A working cash flow forecast with formulas, not a picture of a table.
• Exports what the lender needs. A Word or PDF plan and a slide deck from the same content.
• Builds what comes next. When the plan is funded, Jobbit can build the website and the booking page too. The free plan gives 100 credits a day, and Go is £7 a month.

For ideas on what to hand over after launch, see the 12 AI use cases that pay off for small businesses.

Mistakes that sink a plan

• Asking for "a business plan" in one prompt. You get an essay about a business that does not exist.
• Market numbers with no source. The most common way AI plans embarrass their owners.
• No pay for yourself. A forecast that only works if you live on nothing is not a forecast.
• One version of the future. Sales are always later and lower than planned. Show that you know.
• Writing it once. Open the forecast every month and replace the guesses with what happened.

Frequently asked questions

Can AI write a business plan for me?

It can draft every section, do the research and build the forecast spreadsheet, and that saves days. It cannot supply your prices, your costs or your customers, so the best results come from letting it interview you first and checking every figure it finds.

Will a bank or lender accept a business plan written with AI?

Lenders judge the plan, not the tool. What matters is that the numbers are realistic, the sources are real and you can explain all of it yourself. A plan you cannot defend in conversation fails however it was written.

What should a business plan include?

GOV.UK says it should cover your objectives, strategies, sales, marketing and financial forecasts. In practice that means ten sections: summary, the business, customers, market, marketing, operations, pricing, sales forecast, cash flow forecast, and risks and funding.

Is there a free business plan template?

Yes. GOV.UK links free templates from The King's Trust and from Start Up Loans, and Start Up Loans also provides a free cash flow forecast template. The ten-section table above follows the same shape.

How much can I borrow with a Start Up Loan?

Between £500 and £25,000 at a fixed 7.5% a year, repaid over 1 to 5 years. You need to be 18 or over with a UK business that has traded for less than 5 years, and you will need a business plan.

What is the fastest way to get a plan I can actually use?

Let an agent interview you, research the market with sources and build the forecast, then check the numbers yourself. Start free on Jobbit with 100 credits a day and no card.