How to Write a Startup Budget for a New Business
A startup budget answers two questions before you spend real money: how much do you need to open the doors, and how long can you keep going until sales cover your costs? This guide walks you through writing one, step by step, from launch costs to monthly burn and runway. It is general information, not financial advice, so check your figures with an accountant before you commit.
Key takeaways
- A startup budget has three parts: launch costs, monthly operating costs and runway.
- Runway is how many months your cash lasts at your expected loss. Plan for sales to start slower than you hope.
- Build three scenarios, cautious, expected and good, and fund the cautious one.
- Once you launch, switch to a regular operating budget and compare it with actual results every month.
An operating budget for an established business starts from last year's numbers. A startup budget has no history to lean on. You are estimating costs you have never paid and sales you have never made, which is exactly why it matters. A clear startup budget shows you how much money you need to raise or save, which costs you can delay, and the point at which you should stop and rethink if sales do not arrive.
The process below works for a solo freelancer and for a small shop with staff. The difference is only the number of lines.
What a startup budget covers
A startup budget is different from the ongoing budget you will use once you are trading. It covers the period from today until your business reaches break-even, and it has three parts:
| Part | What it includes | Question it answers |
|---|---|---|
| Launch costs | One-time spending before and at opening | How much do I need to open? |
| Monthly operating costs | Recurring costs once you are trading | How much does the business burn each month? |
| Revenue forecast and runway | Expected sales by month and the cash cushion that covers losses | How long can I keep going until sales cover costs? |
Add those together with a contingency buffer and you get your total startup funding need: the amount you should have in place before you launch.
Common mistake
Budgeting only for launch day. Many founders carefully price equipment and branding, open with nothing left in the bank and then struggle to pay rent in month two. The months before break-even are usually where the money runs out, not opening day.
Step 1: List your launch costs
Start with everything you must pay once before or at opening. Work through these groups and write each item on its own line:
- Legal and admin: business registration, licenses, permits, professional advice.
- Premises: deposit, first month's rent, fit-out, furniture, signage.
- Equipment: computers, tools, machinery, vehicles.
- Inventory: opening stock and raw materials.
- Brand and marketing: logo, website, photography, launch promotion.
- Systems: point-of-sale, accounting software setup, phone and internet installation.
For each line, record the amount, whether it is a quote or a guess, and when it must be paid. Replace guesses with quotes as you go. If you already own an item, leave it out rather than inflating the budget.
Pro tip
Add a "must have" or "can wait" column. Separating essentials from nice-to-haves gives you an instant way to cut the budget if your funding falls short, without dropping anything you truly need to trade.
Step 2: Estimate monthly operating costs
Next, list what the business will cost to run each month once it is open. Split these into fixed and variable costs:
Fixed costs
These stay roughly the same whatever you sell: rent, insurance, software subscriptions, phone and internet, salaries, loan repayments, accounting fees and your own owner's pay if the business must cover it.
Variable costs
These rise and fall with sales: materials, packaging, shipping, payment processing fees, sales commissions and restocking. Express them as a cost per sale or a share of revenue, so they scale correctly in your forecast.
Your total fixed costs plus variable costs at expected sales gives you your monthly costs. The fixed part is your minimum monthly burn: what you lose each month if you sell nothing at all.
Step 3: Forecast revenue month by month
New businesses rarely hit full sales in month one. Build a month-by-month forecast for at least the first 12 months, starting low and ramping up. Base it on evidence wherever you can:
- Estimate customers. How many customers can you realistically reach each month, from pre-orders, a waiting list, enquiries or foot traffic?
- Estimate conversion. What share of them will buy? Use any testing you have done, such as a pilot, a market stall or early orders.
- Set your average sale. Use your planned prices and a realistic mix of products or services.
- Add timing. Account for seasonality, slow starts and payment delays if clients pay on invoice terms.
- Subtract variable costs. This shows the contribution each month's sales make toward fixed costs.
Step 4: Calculate your runway
Runway is the number of months your cash will last while the business is losing money. To calculate it, compare each month's revenue contribution with your fixed costs. The gap is your monthly loss. Add up the losses until the month you expect to break even. That total, plus your launch costs and a buffer, is the cash you need.
Example
Imagine a founder opening a small studio offering design services, with made-up figures. Launch costs are $8,000. Fixed costs are $3,000 a month. The forecast shows contribution of $500 in month one, rising by $500 a month, so the monthly loss shrinks from $2,500 to $2,000, $1,500, $1,000 and $500, reaching break-even in month six. Total losses come to $7,500. Add launch costs and the founder needs $15,500, plus a buffer. If sales start more slowly, the losses and the funding need both grow, which is why the cautious scenario matters.
Three scenarios, not one
A single forecast hides risk. Copy your sheet three times and change the assumptions:
- Cautious: sales start later and grow more slowly; some costs come in higher.
- Expected: your best honest estimate.
- Good: sales arrive sooner and grow faster.
Plan your funding around the cautious case. If you can survive that, you are well placed. If you cannot, you know in advance that you need more money, lower costs or a slower launch.
Step 5: Add a buffer and set your funding target
Startups almost always meet surprises: a permit takes longer, a supplier raises prices, a key piece of equipment breaks. Add a contingency buffer on top of your total. Many founders use a percentage of total costs, and some prefer a fixed number of extra months of fixed costs. Either way, write the reason for your choice next to the figure.
Your funding target is then:
- Launch costs
- Plus cumulative losses until break-even in the cautious scenario
- Plus your contingency buffer
Compare this target with what you have saved and what you can realistically raise. If there is a gap, go back to your "can wait" column, look for ways to lower fixed costs, or consider a smaller first version of the business.
A simple startup budget template
You can build this in any spreadsheet. A basic layout uses one tab for each part:
| Tab | Columns |
|---|---|
| Launch costs | Item, group, amount, quote or estimate, must have or can wait, payment date |
| Monthly costs | Item, fixed or variable, amount or rate, start month |
| Revenue forecast | Month, customers, average sale, revenue, variable costs, contribution |
| Cash and runway | Month, opening cash, cash in, cash out, closing cash |
The cash tab is the most important. It shows the lowest point your bank balance reaches. If that point is close to zero in the cautious case, your plan is fragile.
Common startup budget mistakes
- Leaving out the owner's pay. If you need income from the business, budget for it.
- Assuming customers pay immediately. Invoice terms and marketplace payouts delay cash.
- Forgetting taxes. Sales taxes, payroll taxes and income tax on profits all need cash. Check what applies where you operate.
- Ignoring annual costs. Insurance, license renewals and software paid yearly can create a sudden bill.
- Treating the budget as finished. A startup budget is a living document until you launch.
From startup budget to operating budget
Once you open, your startup budget becomes the first draft of your ongoing operating budget. Each month, compare actual sales and costs with your forecast. If you are behind the cautious case for two or three months in a row, act early: cut costs, change your marketing or adjust your offer before the cash runs low. If you are ahead, resist the urge to spend the surplus straight away until the trend is clear.
Your startup budget checklist
- List all one-time launch costs with quotes where possible
- Mark each launch cost as must have or can wait
- List fixed and variable monthly costs, including your own pay
- Forecast revenue month by month for at least 12 months
- Build cautious, expected and good scenarios
- Calculate cumulative losses until break-even in the cautious case
- Add a contingency buffer and set your funding target
- Check the lowest cash point on your cash tab
- Review the plan with an accountant before you commit funds
Frequently asked questions
What is the difference between a startup budget and a business plan?
A business plan explains what you will sell, to whom and how. A startup budget turns that plan into numbers: what it costs to launch and how much cash you need until the business pays for itself. Most business plans include a startup budget as one section.
How many months of runway should I plan for?
There is no fixed number. It depends on how quickly you expect to reach break-even in your cautious scenario. Plan enough runway to get there, plus a buffer, rather than picking a round number.
Do I need special software to make a startup budget?
No. A spreadsheet is enough for most small businesses. Accounting software becomes useful once you are trading and want to compare actual results with your budget.
What if my funding target is more than I can raise?
Look for ways to start smaller: delay "can wait" items, test the idea before signing a lease, pre-sell to customers or keep a part-time job while you build. A smaller, funded launch is usually safer than a bigger, underfunded one.
Related reading
The bottom line
A startup budget brings together launch costs, monthly costs and a realistic revenue forecast to show how much cash you need before your business can stand on its own. Build cautious, expected and good scenarios, fund the cautious one, add a buffer and track your actual results against the plan every month.
Costs, taxes and rules vary by location and change over time, so treat your budget as an estimate and review it with an accountant or adviser before you commit savings or take on debt.
