Cash Flow Projection Calculator

A cash flow projection turns your recurring monthly income and expenses into a month-by-month view of how much cash you will actually have.

It answers the question a profit number can't: will the balance stay positive every month, or does cash run out before the year is up?

What cash do you have now?

Your starting cash and the reserve you never want to drop below.

Opening balance

Cash actually in the bank today, before any of the months below.

Minimum cash reserve

The cash cushion you never want to fall below. Leave at 0 if you have no set floor.

Projecting 24 months ahead. Set a line's end month for one-offs or seasonal items.

What money comes in?

Actual money received, not invoices raised. Add a line per income stream.

Label	Amount / month	Start	End	Growth %/mo
	£			%

What money goes out?

Recurring bills: rent, payroll, overheads, regular stock. Money leaving every month.

Label	Amount / month	Start	End	Growth %/mo
	£			%

Tip: a one-off is a line whose start and end month match.

What big one-off events matter?

A stock PO, freight and duty, a tax bill, or a deposit — large costs that land in a single month.

Event	Amount	Month
	£
	£

What could go wrong?

Stress-test the plan against one bad month. If the base case survives but the bad month doesn't, the deal is riskier than it looks.

Pick a bad-month scenario to stress-test:

Testing: Damaged shipment

A one-off £50,000 loss in Month 4.

Shock amount

Month it hits

Live result

Updates as you type

Viable but risky

Lowest point: £500
Lowest month: Month 1
Cash payback month: Month 4
Months below zero: 0
Stress low point: £-28,905.60
Stress test impact: £-29,405.60

Jump to full result

Read your result

The verdict, the numbers behind it, and what to do next.

Viable but risky

This works on paper, but cash gets tight before customers pay.

Why the model says this

The dangerous month is Month 1, where cash falls to £500 — money goes out before collections catch up.
The bad-month scenario turns the balance negative (£-28,905.60 in Month 4) — the plan can't absorb that shock as-is.

What to watch

Months below zero: 0.
Cash recovers to your opening level in Month 4.

What to do next

Ask customers for faster payment terms.
Split the PO into smaller deliveries.
Keep a larger cash reserve.
Re-test with lower sales or later collections.

This is a cash survival check and decision support — not a profit forecast or financial advice.

Ending balance

£272,561

Lowest point

£500

Month 1

Lowest month

Month 1

Cash runway

Stays positive

Cash payback month

Month 4

Safety buffer

£500

Net over horizon

£254,561

Months below zero

Stress test impact

£-29,405.60

Cash balance over time

Testing: Damaged shipment

Lowest point: £500 in Month 1
Cash recovers by Month 4
Stress case turns negative in Month 4
Bad month hits in Month 4

Month-by-month

Risky months are highlighted. The lowest month is marked.

Month	Income	Expenses	Net	Balance	Stress balance	Status
Month 1	£0	£17,500	£-17,500	£500	£500	Lowest
Month 2	£9,000	£2,500	£6,500	£7,000	£7,000	OK
Month 3	£9,360	£2,500	£6,860	£13,860	£13,860	OK
Month 4	£9,734.40	£2,500	£7,234.40	£21,094.40	ShockBelow zero:£-28,905.60	Cash recovered
Month 5	£10,123.78	£2,500	£7,623.78	£28,718.18	Below zero:£-21,281.82	OK
Month 6	£10,528.73	£2,500	£8,028.73	£36,746.90	Below zero:£-13,253.10	OK
Month 7	£10,949.88	£2,500	£8,449.88	£45,196.78	Below zero:£-4,803.22	OK
Month 8	£11,387.87	£2,500	£8,887.87	£54,084.65	£4,084.65	OK
Month 9	£11,843.39	£2,500	£9,343.39	£63,428.04	£13,428.04	OK
Month 10	£12,317.12	£2,500	£9,817.12	£73,245.16	£23,245.16	OK
Month 11	£12,809.81	£2,500	£10,309.81	£83,554.96	£33,554.96	OK
Month 12	£13,322.20	£2,500	£10,822.20	£94,377.16	£44,377.16	OK
Month 13	£13,855.09	£2,500	£11,355.09	£105,732.25	£55,732.25	OK
Month 14	£14,409.29	£2,500	£11,909.29	£117,641.54	£67,641.54	OK
Month 15	£14,985.66	£2,500	£12,485.66	£130,127.20	£80,127.20	OK
Month 16	£15,585.09	£2,500	£13,085.09	£143,212.29	£93,212.29	OK
Month 17	£16,208.49	£2,500	£13,708.49	£156,920.78	£106,920.78	OK
Month 18	£16,856.83	£2,500	£14,356.83	£171,277.61	£121,277.61	OK
Month 19	£17,531.10	£2,500	£15,031.10	£186,308.72	£136,308.72	OK
Month 20	£18,232.35	£2,500	£15,732.35	£202,041.06	£152,041.06	OK
Month 21	£18,961.64	£2,500	£16,461.64	£218,502.71	£168,502.71	OK
Month 22	£19,720.11	£2,500	£17,220.11	£235,722.82	£185,722.82	OK
Month 23	£20,508.91	£2,500	£18,008.91	£253,731.73	£203,731.73	OK
Month 24	£21,329.27	£2,500	£18,829.27	£272,561	£222,561	OK

What do you already know?

You don't need finance training. If you can answer these, you can use this tool.

Each one maps to a step below. Prefer to see it first? Start with the demo numbers.

Next in the deal

Cash pressure changes which deal is actually viable.

If the runway is tight, the fix is usually upstream: a cheaper quote or better terms, or a price that pays back faster. Revisit the supplier quote, then re-check the margin that has to carry the timing.

Compare supplier quotes Re-check the margin

Live result

Updates as you type

Viable but risky

Lowest point: £500
Lowest month: Month 1
Cash payback month: Month 4
Months below zero: 0
Stress low point: £-28,905.60
Stress test impact: £-29,405.60

Jump to full result

Try a worked example

What this example shows

The dangerous month is Month 1: stock and freight go out before collections start. The model recovers once customers pay — check the low point leaves enough buffer.

Use your own scenario

No finance degree needed.

See the timing clearly: when money leaves, when it returns, and whether the deal survives the gap.

Use it before stock purchases, supplier deposits, freight commitments, or payment-term decisions.

What this tool tells you

Cash flow is the actual money moving in and out of your account — not profit on paper.
A deal can be profitable and still dangerous if cash leaves before your customers pay.
This tool shows the timing: when money goes out, when it comes in, and the lowest point in between.
Use it before stock purchases, POs, freight commitments, hiring, expansion, and seasonal buying.

How to read a cash flow projection

Cash flow vs profit — why timing decides survival

Profit on paper can still create cash pain. This projects the runway, not the P&L.

When to use this

Before approving a large PO, planning a seasonal buy, or checking whether payment terms and a one-off hit leave you with enough working capital to survive the gap.

Inputs explained

What each field expects

Opening balance
Cash in the bank at the start of month one.
Monthly inflows
Customer collections — money actually received, not invoiced.
Monthly outflows
Rent, payroll, regular stock — when cash actually leaves.
One-off events
A PO, freight & duty, a tax bill, or a deposit that lands in one month.
Stress test
One bad month — a late payment or a damaged shipment — to test the downside.

What the output tells you

How to read each number

Lowest cash point
The month and amount where the bank is thinnest. Plan for this, not the average.
Cash payback month
When early outlays have been recovered by collections.
Safety buffer
How far the low point stays above zero or your chosen reserve.
Verdict
Viable, viable-but-risky, or doesn't-clear-the-cash-test — with what to do next.

Worked example

Opening £18,000. A £13,500 PO + £1,500 freight hit in month 1, £2,500/month overheads.
Collections of £9,000/month don't start until month 2.
Month 1 low point: £500 — survivable, but thin. A £50,000 damaged-shipment month turns it negative.

The deal works on paper, but cash gets tight before customers pay. Test better payment timing before approving the PO.

Common mistakes

Mixing invoiced revenue with cash actually collected.
Forgetting VAT/tax timing or supplier deposits.
Assuming customers pay on time instead of on their real terms.
Planning to the average balance instead of the lowest point.
Overlooking the gap when you pay the supplier — deposit, balance, freight — before the customer pays you. That mismatch is the cash gap.

Decision rule

Plan for the lowest cash point, not the average — and check the plan survives one bad month. If it doesn't, change the terms, not the forecast.

Cash Flow Projection: meaning, example, and how to read it

What a cash flow projection means

A cash flow projection turns your recurring income and expenses into a month-by-month view of how much cash you will actually have. It answers the question a profit number can't: will the balance stay positive every month, or does cash run out before the plan pays off?

Cash flow vs profit

Profit is what's left after costs on paper. Cash flow is the real money in your account. A deal can be profitable over a year and still leave you short in a specific month — because stock, freight, and tax often go out before customers pay. This is a cash survival check, not a profit forecast.

Why timing matters

The danger is almost never the total — it's the timing. If £15,000 leaves in month 1 and £9,000 only starts arriving in month 2, the gap in between is where businesses get caught. The lowest point is the number that decides whether you can afford the deal.

How to enter your numbers

Opening balance: the cash you have today, before the months below.
Recurring income: customer collections per month. Use growth for a ramping line; set start/end months for seasonal income.
Recurring expenses: rent, payroll, overheads, regular stock.
One-off events: a stock PO, freight & duty, a tax bill, or a deposit — each lands in a single month.

How to test a bad month

Real plans meet late payments, damaged shipments, freight spikes, and early tax bills. The stress test layers one of those onto your plan so you can compare the base case against the downside. If the base case survives but the bad month doesn't, the deal is riskier than the headline numbers suggest.

How to read the result

Lowest point: the thinnest your cash gets, and the month it happens.
Cash runway: the first month the balance would go below zero, if any.
Cash payback month: when early outlays (stock, freight, deposits) have been recovered by collections.
Safety buffer: how far the low point stays above zero or your reserve.

Sales break-even (the sales needed to cover costs) is a profit question and a different tool. Don't confuse accounting break-even with cash survival: a profitable month can still be a negative-cash month.

What to do if the model says risky

A risky or not-ready verdict isn't a no — it's a prompt to change the terms. Ask customers for faster payment, split the PO into smaller deliveries, delay the stock purchase until collections start, negotiate supplier credit, keep a larger reserve, or arrange short-term financing before you commit. Then re-test. This is decision support, not financial advice.

What this tool does not do

Pull figures from your accounting system or bank — every line is entered by hand.
Convert currencies — enter everything in one currency.
Model tax, VAT timing, or interest automatically.
Replace a full financial forecast or professional accounting advice.

About Cash Flow Projection

A cash flow projection turns your recurring monthly income and expenses into a month-by-month view of how much cash you will actually have.

It answers the question a profit number can't: will the balance stay positive every month, or does cash run out before the year is up?

When to use it

Budgeting a new product line, container buy, or supplier commitment.
Checking how many months of runway you have at the current burn rate.
Stress-testing a price increase, new hire, or financing cost against the balance.
Planning around seasonal income with per-line start and end months.

Calculation logic

The calculator uses these practical rules:

Monthly net = total income that month − total expenses that month.
Running balance = previous balance + monthly net (starting from the opening balance).
A line with growth compounds from its start month: amount × (1 + growth%)^(month − start).
Cash runway is the first month the running balance drops below zero.

Worked examples

Example

Runway from a starting balance

Opening balance: $20,000
Income: $8,000/mo
Expenses: $10,000/mo

Each month loses $2,000, so the balance falls 20,000 → 18,000 → 16,000 …

Cash runs out in month 11 — the first month the balance goes negative.

How to use the cash flow projection

Start with your opening cash balance, then add the recurring income and expense lines you expect each month.

Use the start and end month on a line for seasonal or temporary items, and the monthly growth percentage for income or costs that ramp over time.

Read the running balance column and the chart to see whether cash stays positive across the full 24 months.

Why cash flow differs from profit

Profit can look healthy while cash runs dry: a large stock purchase, a tax payment, or a slow-paying customer all hit cash before they hit the profit line.

A rolling balance projection exposes the month where cash actually runs out — your runway — so you can act before it happens by adjusting payment timing, financing, or order size.

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Frequently asked questions

Is this profit or cash?

Cash. It tracks money in and out of the balance each month, not accrual profit. A profitable month can still be cash-negative if expenses land before income.

How do I model a one-off cost or income?

Set the line's start month and end month to the same month, so it applies once.

How does growth work?

Growth is an optional monthly percentage that compounds from the line's start month — useful for ramping sales or rising costs.

Does it save my numbers?

No. Everything stays in your browser for the session and is never stored or shared.

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Disclaimer. These tools provide estimates for general informational purposes only. They are not financial, tax, customs, legal, or professional advice. Always verify calculations with your accountant, customs broker, freight forwarder, or relevant professional before making business decisions.