12 Month Cash Flow Forecast
Enter your opening balance and add lines for money coming in and going out. The table shows each month, the closing balance and the first month you run short. Export it as a spreadsheet file.
Worked examples
A simple year
Opening £5,000, sales £4,000, rent £1,500, insurance £1,200 in month 3, tax £3,000 every 3 months from month 4
£24,800 after 12 months
£5,000 + 12 x (£4,000 - £1,500) - £1,200 - 3 x £3,000 = £24,800. The balance never falls below £7,500.
Costs with no income
Opening £1,000, rent £600 a month
Below zero in month 2
The balance is £400 after one month and minus £200 after two, and ends the year at minus £6,200.
Growing sales
£1,000 a month growing 10%
£1,210 in month 3
Growth compounds each month after the start month.
About 12 Month Cash Flow Forecast
A cash flow forecast shows what will be in your bank account at the end of each month. It is different from a profit and loss account, which can look healthy while the bank balance is running down: a customer pays 60 days late, a big VAT bill is due, or a quarterly cost lands in the same month as a slow week. Knowing this a few months ahead leaves time to chase invoices, delay a purchase or arrange an overdraft on good terms.
Start with the balance in the bank, then add lines for money coming in and going out. Each line has an amount, a start month, how often it repeats and a monthly growth rate if it is rising or falling. The table lays out every month, adds up money in and out, and shows the closing balance, the lowest point and the first month it goes below zero. Download the result as a CSV file for a spreadsheet, or copy it.
How to use 12 Month Cash Flow Forecast
- Enter your opening bank balance and the first month of the forecast.
- Review the example lines, then rename them, or add your own lines for money in and money out.
- For each line choose the amount, the month it starts, how often it repeats and any monthly growth.
- Check the closing balances and the warning, then download the table as a CSV file.
Common uses
- Checking you can cover wages and tax over the next year
- Supporting a loan or overdraft request
- Planning when to buy equipment or take on staff
- Testing a cautious case where customers pay a month late
Sources
Last reviewed 18 October 2026.
Frequently asked questions
What is the difference between cash flow and profit?
Profit is income minus costs, whenever the money moves. Cash flow follows the money in the bank. A business can be profitable and still run out of cash if payments arrive after the bills are due.
How do I show a payment that happens once a year?
Add a line, choose the month it starts and set it to repeat once a year. A one-off payment is set to Once.
How does the growth percentage work?
The amount is multiplied by the growth each month after the start month. Sales of £1,000 growing 10% a month are £1,000, £1,100 and £1,210 in the first three months.
Should I include VAT?
Include VAT in the amounts if it passes through your bank account, and add the VAT payment to HMRC as a line in the month it is due.
How can I build a cautious forecast?
Move your income a month later and keep the costs where they are. If the balance still stays above zero, the plan has some margin.