Most startup business plans are written once, to raise money, then never opened again — which is exactly why so many are useless. A good plan does two jobs: it wins funding, and it's a tool you actually run the business with. Here's how to write one that does both.

The sections that matter

  • The problem and your solution — in plain language, what pain you remove and for whom. If you can't say it in two sentences, keep editing.
  • The market — who your customers are and how many exist. Investors want evidence, not a "1% of a huge market" hand-wave.
  • The model — how you make money, what a customer is worth, and what they cost to acquire. This is where credibility is won or lost.
  • Traction — anything real: early sales, a waitlist, pilots, letters of intent. Proof beats promises.
  • The team — why you're the ones to do this. Investors back people as much as ideas.
  • The financials — see below; the part everyone rushes and everyone gets judged on.

The financials investors actually scrutinise

You don't need a 40-tab model. You need a credible monthly forecast that shows:

  • Realistic revenue with timing — sales aren't cash until they're paid.
  • Costs at their true loaded level — a hire costs ~1.1–1.2× salary once NI and pension are in.
  • Your burn rate and runway — the single most important number, and the one that decides how much you need to raise (see our runway guide).
  • A downside case — showing you've thought about what happens if it's slower than hoped builds more confidence than pure optimism.

The mistakes that get plans binned

  • Hockey-stick revenue with no mechanism — growth needs a stated reason (pipeline, conversion data), not a curve.
  • No idea what a customer is worth — if you don't know your unit economics, investors assume there aren't any.
  • Ignoring the cash timing — profitable on paper, insolvent in reality is the classic startup death.
  • Vague use of funds — "for growth" tells a funder nothing; "£40k to hire two engineers and fund six months of runway to hit X" tells them everything.
Make it investor-ready, then keep it live The plans that raise well are backed by clean, current numbers — which is mostly just bookkeeping you didn't defer. A founder who can produce accurate accounts and a defensible forecast in an afternoon looks like a safe bet; one who can't looks like a risk. That's exactly what we help startups be ready for.

Where we help

We build startup forecasts and cashflow models with real numbers in them, keep them current in FreeAgent, and make sure your figures stand up when an investor or lender pulls them apart — plus the wider Buzz ecosystem for the funding itself via our Swoop portal. Get started from £49 + VAT a month.