The 13-week cash flow: the one report every builder should run

Payroll is due in six weeks and you're not sure it's covered. Most builders run their business off the bank balance — but the bank balance tells you where you were, not where you're headed. The 13-week rolling cash flow forecast is the one report that ends the guesswork: claims coming in, retentions due for release, supplier payments, wages, super and tax lumps — week by week, a full quarter ahead.

Thirteen weeks is not an arbitrary number. It is one quarter — long enough to contain a full BAS cycle, a retention release and the back end of most progress-claim cycles, and short enough that the numbers in it are still real rather than guesses. Beyond thirteen weeks you are forecasting; inside it you are planning.

FAQ

What is a 13-week cash flow forecast?

A 13-week cash flow forecast is a rolling, week-by-week projection of every dollar expected in and out of the business over the next quarter — progress claim receipts, retention releases, supplier and subcontractor payments, wages, super, BAS and tax. It is built on project timing rather than accounting periods, which is why it works for builders when a standard cash flow statement does not.

Why 13 weeks and not 12 months?

Thirteen weeks is one quarter — long enough to capture a full BAS cycle, a retention release and most progress-claim cycles, but short enough that the inputs are still knowable rather than guesswork. Twelve-month forecasts are useful for strategy; they are far too coarse to tell you whether next month's payroll clears.

How often should a builder update the forecast?

Weekly, and it should roll — each week drops off the front and a new week thirteen is added at the back. A forecast updated monthly is a document; updated weekly it becomes a decision tool, because you see a shortfall six weeks out while you still have options.

What's the most common mistake in construction cash flow forecasting?

Using invoice dates instead of realistic payment dates. If your claims contractually pay in 30 days but historically land in 55, the forecast has to say 55. The second most common mistake is leaving retentions out entirely — they are typically 5 to 10 per cent of contract value and can sit for a year or more.

See a cash crunch before it arrives. Our cash flow forecasting service builds the 13-week forecast and keeps it current. Related reading: why profitable builders run out of cash and the 5 numbers every builder should check monthly. Or book a free strategy session and we'll walk through your cash position live, or call 1300 886 347.