What Is Accounts Payable? And Why It's Not Just "Bills"
What accounts payable really is — a control function over approval, matching and payment timing — with the ledger entries, the three-way match, and the risks it manages.
Accounts payable is what your company owes suppliers for goods and services already received but not yet paid for. On the balance sheet it is a current liability, sitting alongside VAT and payroll obligations.
Calling it "bills" is where companies go wrong. A bill is a piece of paper asking for money. Accounts payable is the function that decides whether that request is legitimate, whether the goods actually arrived, whether the price matches what was agreed, when to pay, and how to record the whole thing — before any money moves. Most payment fraud and most overpayment happen where that function is treated as data entry.
The entries
Registering a supplier invoice for 100 € plus 21% VAT:
| Account | Debit | Credit |
|---|---|---|
| 6209 Administrative expenses | 100 | |
| 2441 VAT receivable | 21 | |
| 4430 Trade payables | 121 |
The expense is recognized now, when the resource was consumed — not when the cash leaves. The input VAT becomes recoverable at the same moment, which is why registering supplier invoices promptly is a cash-flow decision, not just bookkeeping hygiene: unregistered invoices are unclaimed VAT.
When the invoice is paid:
| Account | Debit | Credit |
|---|---|---|
| 4430 Trade payables | 121 | |
| 2710 Bank | 121 |
The liability disappears, cash falls, and no expense is recorded — that already happened.
If the purchase is inventory rather than a service, the debit goes to stock instead of expense, and the cost only reaches the income statement when the goods are sold. That distinction is the whole reason gross margin works; see gross profit vs operating profit.
Why it's a control function
Between a supplier's invoice arriving and money leaving, four questions need answers:
- Did we order this? An invoice with no corresponding purchase order is either an unauthorized purchase or someone else's invoice.
- Did we receive it? Ordered is not received. Paying for undelivered goods is the most common expensive mistake in payables.
- Is the price right? Suppliers invoice at list price, apply the wrong discount, or quietly change terms.
- Have we paid this already? Duplicate payment happens most often with the same invoice arriving twice — once by email, once with the goods.
The three-way match answers the first three at once by comparing purchase order, goods receipt and invoice. Nordlet implements it: POST /v1/purchases/invoices/match compares an invoice against its linked order line by line and returns a verdict per line — matched, not_on_order, not_received, over_invoiced or price_mismatch, with a configurable price tolerance so trivial rounding differences don't block payment. The mechanics are covered in What Is a Purchase Order?.
The fourth question is answered by the ledger itself: purchase invoices are unique per supplier and document number, so registering the same invoice twice is rejected rather than silently duplicated.
Payment timing is a financing decision
Payables are the cheapest financing most companies have — supplier credit at 0% interest. Every day you legitimately hold cash is a day you don't need a loan. That makes the payment run a real decision with three constraints:
- Terms. Paying a 30-day invoice on day 3 gives the supplier a free loan.
- Early-payment discounts. "2/10 net 30" — 2% off for paying 20 days early — is worth roughly 36% annualized. Taking that discount is almost always right, and the arithmetic surprises people.
- Relationships and law. Late payment has a legal cost in the EU: Directive 2011/7/EU on combating late payment entitles creditors to statutory interest and a recovery fee, and several member states impose stricter limits on B2B payment terms. Stretching suppliers is a strategy with a bill attached.
The balance you are managing shows up directly in working capital: payables are the one current liability that funds the business rather than draining it.
Where the risk is
- Invoice fraud. The dominant form is not a fake supplier but a real supplier's bank details changed by an email that looks like theirs. The defence is verifying bank-detail changes out of band, never from the email requesting them.
- Unrecorded liabilities at period end. Goods received in December, invoice arriving in January, nobody accrues it: December's profit is overstated and the accounting period closes wrong. This is what accrual adjusting entries are for.
- Approval bottlenecks. Invoices stuck awaiting approval turn into late payment, damaged relationships and lost early-payment discounts, and they hide the true liability until they surface.
- Missed input VAT. Invoices registered after the VAT return is filed push recoverable VAT into a later period, or lose it.
What the product does
Supplier invoices are registered through POST /v1/purchases/invoices/create and posted with /invoices/register, which is when the ledger entries above are written and the input VAT enters the VAT return. Documents can arrive by OCR capture rather than typing.
On the payment side, POST /v1/bank/payments/export produces a SEPA pain.001 credit-transfer file for selected open invoices, which the bank executes; the resulting statement is imported and matched back against those invoices, closing the loop. Outstanding balances are visible through POST /v1/reports/debt-aging { side: 'payables' } with the same buckets used for receivables, described in aging reports.
Two things not implemented today, stated plainly: there is no approval-workflow engine (an invoice is draft or registered — multi-step approval chains live in your own process), and no automatic duplicate-detection beyond the supplier-plus-document-number uniqueness constraint.
FAQ
Is accounts payable an expense?
No. The expense is recorded when the goods or services are received; accounts payable is the liability created at that moment and cleared when you pay. Paying an invoice never creates an expense — it only settles one already recorded.
What is the three-way match?
Comparing three documents before paying: the purchase order (what was agreed), the goods receipt (what arrived) and the supplier invoice (what is being charged). If all three agree within tolerance, the invoice can be paid without a human judgment call; if they don't, the discrepancy is exactly what needs review.
What is the difference between accounts payable and accrued expenses?
A payable is backed by a supplier invoice you have received. An accrued expense covers something consumed but not yet invoiced — December electricity billed in January. Both are liabilities; the difference is whether the document exists yet.
Should I pay suppliers as early as possible?
Only when there is a discount worth taking or a relationship reason. Otherwise paying on the due date is correct: supplier credit is interest-free financing, and using it is not sharp practice as long as you pay on time.
Does accounts payable include VAT?
Yes — the payable is the gross amount you owe the supplier, VAT included. The VAT element is separated at registration into a recoverable input-VAT asset, which is why the expense and the liability differ by exactly the VAT.