Build a Progress Invoicing Schedule Around Project Cash Costs

Start with the costs you cannot move easily

List the project commitments before choosing invoice percentages: supplier payments, subcontractor instalments and the payroll cash attributable to the work. Put each amount in the week money leaves the bank. A purchase order placed in week 1 with payment due in week 3 belongs in your commitments list immediately, but its cash outflow belongs in week 3.

Use the cash-flow forecast template for the wider business. This project schedule is a supporting view; it should not quietly exclude the rent, tax payments or other jobs competing for the same bank balance.

Business Victoria's forecasting guidance starts from opening cash and adds receipts less outgoings for each period. Timing is the point of the exercise. Read its forecasting steps.

Agree the milestones before relying on the money

Choose a result that both sides can identify: an accepted discovery brief, a completed test, delivered drawings or an agreed handover package. "Halfway through" leaves too much room for different interpretations.

For each milestone, record the amount, completion test, required documents, invoice submission method and agreed payment trigger. A planned invoice week is your forecast assumption; it isn't permission to invoice before the agreed work or condition is met. business.gov.au recommends making milestone results, amounts, acceptable work and payment timing clear in the contract. Prepare a contract: payment details.

Keep a slot for the customer's acceptance contact and your own document owner. Assign someone to collect the evidence before the invoice is prepared. Check the final document against tax invoice requirements before sending it.

Plot a six-week service project

In this fictional example, a design business has agreed a $24,000 project with three milestones. Expected receipts follow invoicing by one week because that is the documented assumption for this fictional customer. It is not a recommended payment term or an industry rule.

Assumptions: Fictional professional-services project, AUD cash totals. No borrowing, separate tax remittances or whole-business overheads included. Full business forecast must include those amounts.

Milestone and invoice week	Amount	Evidence to assemble before billing	Expected receipt
W1: discovery brief accepted	$6,000	Dated brief version; customer acceptance; order reference	W2
W3: working prototype accepted	$8,000	Test record; prototype link; acceptance email; invoice receipt	W4
W5: final files handed over and accepted	$10,000	Handover list; delivery record; acceptance; submission reference	W6

Original ASBG fictional example. Use the assumptions above when replacing these figures with your own.

The business allocates $5,000 of opening cash to the project. Project payments are $4,000, $3,500, $3,500, $4,000 and $3,000 across weeks 1 to 5, then zero in week 6: $18,000 in total. These are cash amounts, including any GST already in the relevant bill or invoice, not revenue-recognition or GST-remittance calculations.

Assumptions: Fictional professional-services project, AUD cash totals. No borrowing, separate tax remittances or whole-business overheads included. Full business forecast must include those amounts.

Week	Cumulative invoices	Cumulative expected receipts	Cumulative committed payments	Base closing cash from $5,000
1	$6,000	$0	$4,000	$1,000
2	$6,000	$6,000	$7,500	$3,500
3	$14,000	$6,000	$11,000	$0
4	$14,000	$14,000	$15,000	$4,000
5	$24,000	$14,000	$18,000	$1,000
6	$24,000	$24,000	$18,000	$11,000

Original ASBG fictional example. Use the assumptions above when replacing these figures with your own.

By week 3, the project has invoiced $14,000 but received only $6,000. Against $11,000 of payments, the allocated cash is $5,000 + $6,000 − $11,000 = $0. The later receipt won't cover a payment that falls due in week 3. Check the days within each week too; a supplier paid on Monday cannot use money arriving on Friday.

The project ends with $11,000 in this simplified cash view. That is opening cash plus the $6,000 excess of project receipts over the included payments. It is not the business's profit or freely spendable surplus: the full forecast still needs overheads, tax remittances and other commitments.

Test an approval delay, not just a lower sales number

Suppose prototype acceptance is delayed and the $8,000 receipt moves from week 4 to week 5. Keep the committed payments where they were. If the work delay would also move costs or final handover, test that as an additional scenario rather than quietly changing this one.

Assumptions: Fictional professional-services project, AUD cash totals. No borrowing, separate tax remittances or whole-business overheads included. Full business forecast must include those amounts.

Week	Base receipt	Delayed-case receipt	Base closing cash	Delayed closing cash
1	$0	$0	$1,000	$1,000
2	$6,000	$6,000	$3,500	$3,500
3	$0	$0	$0	$0
4	$8,000	$0	$4,000	−$4,000
5	$0	$8,000	$1,000	$1,000
6	$10,000	$10,000	$11,000	$11,000

Original ASBG fictional example. Use the assumptions above when replacing these figures with your own.

Week 4 now reaches −$4,000. If the owner chooses an illustrative $2,000 minimum cash floor, the gap against that floor is $6,000. The final balance is unchanged, which shows why checking only the project total misses the problem.

Before accepting the job on these assumptions, investigate whether the milestone can be evidenced earlier, whether a different billing arrangement can be agreed, or whether supplier timing and available funding can cover the gap. Record a proposed change separately until it is agreed. For broader tests, use the guide to a large customer paying late.

Check construction projects separately

This forecast follows an ordinary service project. Construction work needs a separate check of the rules applying to the project and location before dates are entered. Take the contract, claim history and proposed milestones to a construction lawyer, and ask them to identify the documents and deadlines you need to track. Building Commission NSW's security-of-payment page is a starting point for NSW work; use the relevant authority elsewhere.

Keep any verified claim or response deadlines in separate columns from your expected bank receipts. The spreadsheet models cash timing; it supplies no contractual terms or statutory claim timetable.

Update evidence and receipts together

Review the schedule with the project lead each week. Record milestone status, missing evidence, invoice reference, submission acknowledgement, expected receipt and actual bank receipt. If an approval moves, update the forecast and give the next action to a named person.

That review belongs inside the regular cash-flow routine. Find related tasks in cash flow and getting paid.

Next, find finished work that has not reached the invoice list.

Key takeaways

• Pair each agreed milestone with an amount, evidence owner and realistic receipt date.
• Compare receipts with committed payment dates, not just total project margin.
• Move an approval-dependent receipt to test the temporary cash gap.
• Check industry and jurisdictional requirements before using the schedule for a real contract.

Where to get help

• business.gov.au: prepare a contract for milestone and payment-detail questions.
• Business Victoria: cash flow forecasting for the cash calculation method.
• Building Commission NSW: security of payment for NSW construction guidance; use the relevant authority and a construction lawyer for work elsewhere.