CASH-FLOW GUIDE · UPDATED SEPTEMBER 2026
The 13-week cash-flow forecast: your balance sheet, unwound by date
A company’s bank balance is usually at its highest on the day before it stops being. Payroll, GST and rent do not arrive as averages; they arrive on dates, and several of them arrive in the same week. A 13-week forecast is not a prediction of how the business will do. It is a calendar of what will leave the account and when, set against what is realistically coming in — built from the receivables, payables and statutory dates you already have.
THE STARTING POINT
Every line already exists on your balance sheet.
A forecast is not invented. Receivables are receipts that have not happened yet; payables are payments that have not happened yet; the GST control account is one payment on a known date. The forecast takes the balance sheet as it stands today and unwinds it, line by line, into the weeks in which each balance will turn into cash. That is why it starts from reconciled books, and why a company that cannot produce a balance sheet it trusts cannot produce a forecast it trusts either.
The debtors ledger, aged and dated by behaviour
Every open invoice is a receipt waiting for a date. The date is not the one on the invoice — it is the one that customer actually pays on. A customer on 30-day terms who has paid at day 52 for the last six invoices is a day-52 receipt, and the forecast should say so. This one column of the forecast decides whether the whole thing is worth reading.
The creditors ledger and the committed spend
Supplier bills already received, by due date. Then the outflows that have no bill yet but are certain: payroll, CPF, rent, loan repayments, subscriptions, the insurance renewal. A forecast that only contains what is in the purchase ledger will miss most of what leaves the account.
The statutory calendar
GST, CPF, the corporate tax instalment, the annual return. None of these is negotiable, all of them fall on dates that are known months in advance, and the largest of them — the quarterly GST payment — is money that was never yours in the first place. This is the layer most spreadsheet forecasts leave out entirely.
THE SINGAPORE CALENDAR
Six outflows with fixed dates. Put them in first.
Before any customer is dated or any supplier is listed, these go into the forecast, because their dates are not up to you. Two of them carry a mechanism worth knowing about: GST paid by GIRO leaves two weeks later than GST paid by transfer, and a corporate tax GIRO that fails twice cancels itself and makes the whole balance due at once.
| Outflow | When it leaves | What sets the amount |
|---|---|---|
| GST | One month after each quarter ends: 30 Apr, 31 Jul, 31 Oct, 31 Jan. On a GIRO plan the deduction moves to the 15th of the following month. | Output tax on the quarter's sales less input tax on purchases — the balance on the GST control account. |
| CPF contributions | Due on the last day of the month. Enforcement can follow if not paid by the 14th of the next month; late-payment interest runs at 1.5% a month from the day after the due date, minimum S$5. | Employer and employee contributions on the month's payroll. |
| Corporate tax instalment | GIRO deduction on the 6th of each month. If it fails, IRAS retries on the 20th; if both fail, the GIRO plan is cancelled and the balance is due at once. | Tax on your ECI, spread over up to 10 instalments depending on how early it was filed. |
| Corporate tax on assessment | One month from the date of the Notice of Assessment. 5% penalty on the unpaid amount after that. | The difference between the final assessment and the instalments already paid. |
| Payroll | Whatever the contracts say — usually the last working day of the month, which makes month-end the heaviest week in almost every forecast. | Net salaries after employee CPF; the employer's CPF share follows two weeks later. |
| Annual lumps | Timed from your financial year-end or a renewal date: annual return and secretarial fees, insurance, licences, audit fee, software billed yearly. | Whatever you paid last year, with a date. These are the items that surprise a company because they only happen once. |
A WORKED QUARTER
S$121,000 on 26 April. S$29,000 on 5 July. Nothing went wrong.
Take the same GST-registered distributor from the management accounts guide: about S$2 million a year, eight staff, a bank loan, a December year-end and a corporate tax bill spread over ten instalments. It opens the week of Monday 6 April 2026 with S$95,000 in the bank. Supplier payments run between S$20,000 and S$26,000 a week. Everything else in the table is a dated event. Figures are in S$ and include GST, because cash does.
| Wk | 2026 | In | Out | Closing cash | What lands |
|---|---|---|---|---|---|
| 1 | 6–12 Apr | 36,000 | 31,000 | 100,000 | Tax instalment on the 6th; loan on the 10th |
| 2 | 13–19 Apr | 52,000 | 38,000 | 114,000 | March CPF by the 14th |
| 3 | 20–26 Apr | 28,000 | 21,000 | 121,000 | Suppliers only. Highest balance of the quarter. |
| 4 | 27 Apr–3 May | 31,000 | 94,000 | 58,000 | April payroll and Jan–Mar GST on the 30th; May rent on the 1st |
| 5 | 4–10 May | 25,000 | 30,000 | 53,000 | Tax instalment on the 6th |
| 6 | 11–17 May | 44,000 | 39,000 | 58,000 | Loan on the 11th; April CPF by the 14th. Receipts include one S$38,000 invoice. |
| 7 | 18–24 May | 39,000 | 31,000 | 66,000 | Annual insurance renewal |
| 8 | 25–31 May | 47,000 | 70,000 | 43,000 | May payroll on the 29th |
| 9 | 1–7 Jun | 33,000 | 33,000 | 43,000 | June rent on the 1st |
| 10 | 8–14 Jun | 41,000 | 30,000 | 54,000 | Tax instalment on the 8th (the 6th is a Saturday); loan on the 10th |
| 11 | 15–21 Jun | 30,000 | 40,000 | 44,000 | May CPF on the 15th (the 14th is a Sunday) |
| 12 | 22–28 Jun | 49,000 | 23,000 | 70,000 | Suppliers only |
| 13 | 29 Jun–5 Jul | 38,000 | 79,000 | 29,000 | June payroll on the 30th; July rent on the 1st. Below the S$30,000 floor. |
Three things are visible here that a bank balance cannot show. The balance peaks on 26 April, the day before the heaviest week of the quarter: payroll, the January–March GST payment and May’s rent all leave within five days of each other and take S$63,000 out. An owner checking the account on the 26th feels well funded, and is about to be S$58,000. The quarter then drifts down — not through any single bad week, but because collections are running a little behind supplier payments every week and the annual insurance renewal, a once-a-year item, lands in week 7. And week 13 closes at S$29,000, below the S$30,000 floor, with the April–June GST payment due four weeks past the horizon. That is not a crisis. It is a decision that needs making in May.
Move one invoice by four weeks.
Week 6’s receipts include a single S$38,000 invoice — the same customer who, in the management accounts guide, slipped from 30 days to 60. Suppose they slip again and pay in week 10 instead. Nothing else changes. Weeks 6 to 9 each close S$38,000 lower: S$20,000, S$28,000, S$5,000 and S$5,000. Week 8 is May payroll. One customer being a month late turns a comfortable payroll week into one where a single supplier payment clearing early would bounce it — and the base case gave no warning, because on the base case that invoice was never late. This is why the dating of receipts is the assumption that matters, and why the forecast needs to be built by someone who knows which customers pay when.
HOW TO BUILD IT
Six steps, in this order.
The mechanics are simple enough for a spreadsheet: thirteen columns, an opening balance, receipts, payments, a closing balance that becomes next week’s opening. The discipline is in what goes into each cell and in step six, which is the one most forecasts skip.
01
Start from the reconciled bank balance, not the ledger
Opening cash is what the bank says this morning, less any transfers already issued and not yet cleared. If the bank reconciliation is three weeks behind, fix that first — every later week inherits the error.
02
Date every receipt by how the customer behaves
Take the aged debtors list and put each invoice in the week it will actually be paid, using that customer's history rather than the terms on the invoice. Add sales not yet invoiced only where they are contractually certain — a signed retainer, a deposit due on a milestone. Optimism goes in a separate scenario, never in the base case.
03
List every payment by due date, including the ones with no bill
Creditors by due date, then the committed recurring items, then the statutory calendar above, then the annual lumps. Payroll and CPF are two separate lines two weeks apart. Loan repayments are principal and interest together — the forecast does not care which is which.
04
Keep GST in on every line
The P&L excludes GST. The forecast must include it: customers pay you 109% of the sale, you pay suppliers 109% of the cost, and the difference leaves for IRAS on a known date. A forecast built from P&L figures understates both receipts and payments by 9% and then forgets the quarterly payment entirely.
05
Set a floor
Decide the lowest closing balance you are prepared to see — a week of supplier payments plus a margin is a reasonable start. The floor is what turns the forecast from a spreadsheet into an alarm: any week that closes below it is a decision that needs making now, not then.
06
Roll it every week
Replace last week's forecast with what actually happened, note the variance and why, drop the week that has passed and add week 14. The variance column is where the forecast learns: if receipts keep landing a week late, the dating assumption is wrong, and the next 13 weeks are wrong with it.
WHEN A WEEK CLOSES BELOW THE FLOOR
Four levers, cheapest first.
The forecast’s whole purpose is to surface a bad week while these are still available. Each one gets more expensive, or disappears entirely, the closer the week gets.
Pull receipts forward
Chase the specific invoices the forecast shows are late, not the ledger in general. Ask for deposits on new work and stage payments on long jobs. A small early-settlement discount on one large invoice can be cheaper than an overdraft for the same weeks.
Move payments back — before they are due
A supplier asked for 14 more days a fortnight before the due date usually says yes. A supplier asked on the day it bounced puts you on pro-forma. The forecast's value is that it lets you have the first conversation instead of the second.
Use the timing the tax system already offers
GST paid by GIRO leaves on the 15th of the month after the due date rather than on the due date itself — two extra weeks, at no cost, every quarter. An ECI filed within a month of year-end spreads the tax bill over 10 instalments instead of 6 or none. Neither reduces what you pay; both change when.
Arrange finance while the forecast is still comfortable
A working-capital facility applied for in week 3, when the balance is S$121,000, is a routine conversation. The same application in week 8 is not. Lenders ask for exactly the documents a rolling forecast produces: the forecast itself and recent management accounts.
What the Enterprise Financing Scheme actually offers.
The SME Working Capital Loan under EnterpriseSG’s Enterprise Financing Scheme is the facility most Singapore SMEs end up discussing with their bank. The published terms: up to S$500,000 per borrower, repayable over up to 5 years, with EnterpriseSG taking 50% of the default risk off the bank — and, for all enterprises, 70% from 1 September 2026 to 31 March 2027. The borrower still owes 100% of the loan; the interest rate is the bank’s to set; and the bank makes its own credit decision. Eligibility is broad — at least 30% local equity, group revenue up to S$100 million or up to 200 employees — but the application will ask for a forecast and management accounts, and a bank can tell the difference between a forecast that has been rolled for months and one assembled last week.
Why a director should want this on file.
No regulator asks for a cash-flow forecast. What the law asks is that a company not trade wrongfully. Section 239 of the Insolvency, Restructuring and Dissolution Act 2018 defines that as a company which, when insolvent, incurs debts or other liabilities without reasonable prospect of meeting them in full. An officer who knew, or ought to have known, can be declared personally liable for the company’s debts without limit, and the offence carries a fine of up to S$10,000 or imprisonment of up to 3 years, or both. A rolled forecast, with actuals against it, is the clearest evidence a director can hold that the prospect of paying was reasonable when the debt was taken on.
WHAT GOES WRONG
Five ways a forecast fails to earn its keep.
It is the budget divided by 52
A monthly budget spread evenly across weeks shows payroll as a quarter of itself every week and the GST payment as a twelfth of itself every month. Neither happens. The forecast exists to show the collision of real dates; averaging removes the only thing it was for.
Receipts are dated by invoice terms
If every invoice is forecast to arrive on its due date, the forecast is a description of your terms and conditions, not of your customers. Use behaviour. The management pack's debtor-days figure is the sanity check: if it says 52 and the forecast assumes 30, one of them is wrong.
GST is missing, or counted twice
Missing is the common one: receipts and payments taken from the P&L, so the 9% never enters and the quarterly payment never leaves. Counted twice is rarer but worse — GST-inclusive receipts and a separate quarterly payment line that was built from gross sales rather than the control account.
It was built once
A forecast prepared for a loan application and never touched again is out of date within a fortnight. The rolling is the forecast. If nobody is going to refresh it weekly, do not build it — a stale forecast produces confident decisions on wrong numbers.
It shows a problem and nothing happens
Week 8 closes below the floor and the response is to watch week 8 arrive. The forecast is meant to change a decision in week 2 — which invoice to chase, which payment to move, whether to talk to the bank. If it does not produce an action, it is a very detailed way of worrying.
Common questions.
Why 13 weeks and not 12 or 26?
Thirteen weeks is a quarter, so the window always contains one GST payment, three payrolls, three CPF payments and three tax instalments — every recurring cash event at least once. It is short enough that receipts can be dated invoice by invoice rather than estimated, and long enough to act on what it shows: chasing a debtor or arranging a facility takes weeks, not days. Beyond a quarter, the invoice-level detail runs out and the forecast becomes a budget with weekly columns.
Is a cash-flow forecast a legal requirement in Singapore?
No regulator asks for one. What the law does require is that a company not trade wrongfully: under section 239 of the Insolvency, Restructuring and Dissolution Act 2018, a company trades wrongfully if, when insolvent, it incurs debts without reasonable prospect of meeting them in full, and an officer who knew or ought to have known can be made personally liable and faces a fine of up to S$10,000 or up to 3 years' imprisonment. A current forecast is the practical evidence that a director had a reasonable basis for believing the company could pay its debts as they fell due.
What is the difference between a cash-flow forecast, a budget and a cash-flow statement?
The cash-flow statement in your management accounts looks backwards: it explains where last month's cash went. A budget looks forward a year, by month, in P&L terms — revenue and costs, usually excluding GST. A 13-week forecast looks forward a quarter, by week, in cash terms — receipts and payments including GST, dated by when money moves. The three use different bases and answer different questions; a company running well usually has all three.
Do I include GST in the forecast?
Yes, on every line. Receipts are what customers pay, which includes 9% GST. Payments are what you pay suppliers, which includes their GST. The net difference leaves as a single payment one month after each quarter ends, or on the 15th of the month after that if you pay by GIRO. Leaving GST out understates cash movement in both directions and hides the largest single statutory payment most SMEs make.
What if my bookkeeping is not up to date?
Then the forecast cannot start, because the opening balance, the debtors list and the creditors list are all wrong by whatever has not been entered. Bring the bank reconciliation current first — usually a few days' work for a small company — and build the forecast from that. A forecast on top of unreconciled books is precise about numbers that are not true.
Will a forecast help me get a bank loan?
It is usually a condition of one. Banks assessing a working-capital facility, including loans under EnterpriseSG's Enterprise Financing Scheme, want to see a cash-flow forecast and recent management accounts. The SME Working Capital Loan runs to S$500,000 per borrower over up to 5 years, with EnterpriseSG sharing 50% of the default risk with the bank — raised to 70% for all enterprises from 1 September 2026 to 31 March 2027. The borrower still repays the full loan, and the bank sets the rate. A forecast that has been rolled for a few months, with actuals against it, is far more persuasive than one assembled for the application.
How accurate does it need to be?
Accurate about dates and honest about uncertainty. The near weeks should be close, because they are built from actual invoices and bills; weeks 10 to 13 will be rougher and that is expected. The useful measure is not whether week 8 came out to the dollar but whether the forecast showed the shape of the quarter — the heavy weeks, the trough, the floor breach — early enough to act. If the variance each week is consistently in one direction, the assumption behind it needs changing.
Official sources
GST, corporate tax and ECI payment dates and penalties are as published by IRAS; CPF due dates and late-payment interest as published by the CPF Board; Enterprise Financing Scheme terms as published by EnterpriseSG; the wrongful trading provision as enacted in section 239 of the Insolvency, Restructuring and Dissolution Act 2018. All checked on 22 September 2026. The worked quarter is illustrative.
- IRAS: GST filing and payment due dates, including GIRO deduction dates
- IRAS: Late payment or non-payment of GST
- IRAS: GIRO for Corporate Income Tax (deduction on the 6th, retry on the 20th)
- IRAS: Late payment or non-payment of Corporate Income Tax
- IRAS: Estimated Chargeable Income (ECI) filing and instalments
- CPF Board: Enforcement and penalties for non-compliance
- EnterpriseSG: Enterprise Financing Scheme – SME Working Capital Loan
- Insolvency, Restructuring and Dissolution Act 2018, section 239: Responsibility for wrongful trading
This guide provides general information, not accounting, financing or legal advice. The worked quarter uses illustrative figures. Payment dates, penalty rates and financing scheme terms are as published on the date shown and change from time to time; what your company should forecast, and how it should respond to what the forecast shows, depends on its own circumstances.
WRITTEN BY
Jacqueline May
Principal Accountant · Chartered Accountant (Singapore), in practice since 2008
Jacqueline is a Chartered Accountant (Singapore) and the Principal Accountant at Synergy Accounting, in practice since 2008. She works on corporate tax, GST and ACRA compliance for small and medium businesses — the filings, deadlines and judgement calls most owners would rather hand over. These guides are written from what she sees in practice.