Accounts payable is what your business owes its suppliers. Accounts receivable is what your customers owe you. On your balance sheet, AP sits as a current liability and AR as a current asset.
What most AP-vs-AR explanations miss is how the two interact — and most small business invoice software comparison sites treat the two sides as a single category, leading businesses to buy the wrong tool entirely. The gap between when you pay suppliers (AP) and when customers pay you (AR) is your cash conversion cycle. It determines how much working capital your business ties up just to keep operating. For a construction subcontractor paying material suppliers on 14-day terms while waiting 60 days for progress claims, that gap can lock up hundreds of thousands of dollars.
This guide covers the mechanics, the Australian GST and BAS treatment, and the cash flow dynamics that make managing AP and AR together more important than understanding either one alone. If you want to model the numbers for your own business, use our working capital calculator.
How AP and AR Move Through Your Books
Accounts payable starts when you receive a supplier invoice and ends when you pay it. In between, the invoice gets coded to the right account, matched against a purchase order if one exists, routed for approval, and scheduled for payment. Your AP ledger balance at any point tells you how much you owe across all suppliers.
Accounts receivable starts when you issue a sales invoice and ends when the customer pays. Your AR ledger tells you how much is owed to you. Both follow the same core cycle: a document creates the obligation, time passes, and cash settles it. The difference is direction. AP is cash leaving. AR is cash arriving.
Journal entries with GST
Most AP-vs-AR guides show journal entries without GST because they’re written for a US audience. In Australia, the GST component changes the entry structure.
Recording a supplier invoice (AP) for $11,000 GST-inclusive:
| Account | Debit | Credit |
|---|---|---|
| Expense (e.g. equipment maintenance) | $10,000 | |
| GST receivable (input tax credit) | $1,000 | |
| Accounts payable | $11,000 |
The $1,000 GST component becomes an input tax credit you claim back from the ATO on your BAS.
Recording a sales invoice (AR) for $5,500 GST-inclusive:
| Account | Debit | Credit |
|---|---|---|
| Accounts receivable | $5,500 | |
| Revenue | $5,000 | |
| GST payable | $500 |
The $500 GST is collected on behalf of the ATO and remitted when you lodge your BAS.
Your net GST position flows from the difference between these two sides. A business with more AP GST credits than AR GST collected gets a refund. One with more AR GST collected than AP credits owes the ATO the difference.
AP vs AR: The Differences That Matter
| Accounts Payable | Accounts Receivable | |
|---|---|---|
| What it represents | Money you owe suppliers | Money customers owe you |
| Balance sheet | Current liability | Current asset |
| Cash flow direction | Outflow when paid | Inflow when collected |
| Normal balance | Credit | Debit |
| Key metric | Days payable outstanding (DPO) | Days sales outstanding (DSO) |
| BAS labels | G10 (capital), G11 (non-capital), 1B (input credits) | G1 (total sales), 1A (GST on sales) |
| Risk when unmanaged | Late payment penalties, lost discounts, supplier damage | Bad debts, cash flow squeeze, overdraft dependency |
| Automation focus | Invoice capture, coding, approval routing, payment scheduling | Invoice generation, reminders, collection escalation |
Both sides share one trait: ageing makes them worse. An AP invoice 30 days overdue accrues interest. An AR invoice 90 days overdue has a declining probability of collection. The ASBFEO reports that payment disputes account for 42% of their assistance cases, up from 36% the previous year, with insolvency-related requests up 50%.
The Cash Conversion Cycle: Where AP and AR Meet
The cash conversion cycle measures how many days your business takes to turn its outflows (paying suppliers, holding inventory) into inflows (collecting from customers).
CCC = Days Inventory Outstanding + Days Sales Outstanding - Days Payable Outstanding
A shorter cycle means faster cash generation. A longer cycle means more working capital locked up in the gap between paying and getting paid.
Two businesses, same revenue, different pressure
Wholesale distributor ($5M revenue):
- Holds inventory for 20 days (DIO = 20)
- Customers pay in 35 days (DSO = 35)
- Pays suppliers in 45 days (DPO = 45)
- CCC = 20 + 35 - 45 = 10 days
Cash turns over fast. This business needs roughly 10 days of operating costs funded by working capital.
Construction subcontractor ($5M revenue):
- Materials sit as work-in-progress for 30 days (DIO = 30)
- Progress claims get paid in 65 days (DSO = 65)
- Material suppliers require payment in 14 days (DPO = 14)
- CCC = 30 + 65 - 14 = 81 days
On $5M revenue, 81 days of CCC locks up roughly $1.1M in the cycle at any given time. At current overdraft rates of 9-12%, financing that gap costs $99,000 to $132,000 per year before a single invoice runs late.
The Payment Times Reporting Regulator found that the average large business now takes 64 days to pay 95% of its small business invoices, up from 58 days in the prior reporting cycle. When your customers are large businesses paying slowly, your AR cycle stretches regardless of what your payment terms say.
Australian benchmarks by industry
| Industry | Typical DSO | Typical DPO | Typical CCC |
|---|---|---|---|
| Retail / e-commerce | 5-20 days | 30-45 days | Negative to 10 days |
| Wholesale distribution | 30-50 days | 35-45 days | 5-25 days |
| Professional services | 30-60 days | 20-30 days | 30-50 days |
| Manufacturing | 45-60 days | 35-43 days | 40-70 days |
| Construction | 60-90 days | 14-30 days | 60-120 days |
Sources: CreditPulse 2025 industry benchmarks; Payment Times Reporting Regulator H1 2025 data; ScaleSuite 2026 CCC analysis.
Retail sits at or below zero because customers pay at the register while suppliers offer 30-45 day terms. Construction sits at the other extreme. Retention holdbacks of 5-10% held until practical completion push the effective DSO even further than the progress claim cycle alone.
Where each side breaks
On the AP side, the failure mode is approval bottlenecks. The invoice arrives on time. The cash is available. But the approval workflow takes too long and the due date passes. Late payment penalties accrue, early payment discounts are forfeited, and supplier relationships degrade. The GoCardless Pursuing Payments 2025 survey found that 63% of Australian businesses lose money to late payments, with an average annual loss of $29,000.
On the AR side, the failure mode is collection discipline. Invoices go out on time but nobody follows up systematically when payment is late. Debtor days creep from 30 to 45 to 60. By the time someone notices, the overdue balance is large enough to cause a cash flow problem that could have been prevented with a reminder sent on day 31.
How AP and AR Appear on Your BAS
Accounts payable and accounts receivable feed different sections of your Business Activity Statement.
AR side (what you collected): G1 reports your total sales for the period. 1A reports the GST you collected from customers on those sales. These two labels capture everything flowing through your receivables.
AP side (what you spent): G10 reports capital purchases (vehicles, plant, equipment). G11 reports non-capital purchases (trading stock, office expenses, repairs). 1B reports the total input tax credits you’re claiming back. Under Simpler BAS, which most small businesses use, you only report G1, 1A, and 1B. Full reporting adds the G10/G11 breakdown.
Your net GST position is 1A minus 1B. If you collected more GST on sales than you paid on purchases, you owe the ATO the difference. When your input credits exceed collected GST (common during capital expenditure periods), the ATO owes you a refund.
The accounting detail that causes problems: AP and AR must be coded to the correct tax codes for the BAS to be accurate. A supplier invoice coded as GST instead of CAP for a capital purchase flows through to G11 instead of G10. A GST-free supply coded with GST creates a phantom input credit. Neither error is visible until the ATO audits. For a breakdown of which tax codes apply to which purchase types, see our BAS worksheet generator.
Managing AP and AR Together
Most businesses run AP and AR as separate functions. Different teams, different tools, different KPIs. That works until cash tightens.
Track both aging schedules in the same weekly review. Your AP aging report tells you what’s going out. Your AR aging report tells you what should be coming in. Looking at one without the other is how cash flow surprises happen.
Match your payment terms to your collection terms where possible. If customers pay you on 45-day terms, negotiating 45-day terms with your suppliers eliminates the CCC gap on those transactions. When customers are on 30-day terms but routinely pay in 50, your effective DSO is 50, and your AP payment schedule needs to reflect the reality, not the contract.
For most industrial businesses, AP is the higher-value automation target: more invoices, more approval delays, contractual penalties for late payment. Service businesses often find AR is the bigger gap, with fewer invoices but longer collection cycles and higher bad-debt risk. Pulsify’s AP automation handles the payables side. Your cash flow forecast and DSO calculator can quantify which side needs attention first.
Sources: Payment Times Reporting Regulator - January 2026 Update · GoCardless - Pursuing Payments 2025 · ASBFEO - Payment Dispute Assistance Cases · CreditPulse - DSO by Industry 2025 · ScaleSuite - Cash Conversion Cycle for Australian SMEs 2026 · ATO - Simpler BAS GST Bookkeeping Guide
Further reading: Overdue Invoice Automation Australia · Payment Scheduling, Early Discounts and Cash Flow · Construction Bookkeeping: Invoice Controls · How to Calculate Late Payment Interest