Glossary

Financial & invoicing terms explained

Quick definitions for AR/AP teams, founders, and operators—aligned with how modern invoicing software works.

Accounts receivable (AR)

Money customers owe you from issued invoices.

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Accounts payable (AP)

Money your business owes suppliers from their bills.

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Balance due

Remaining unpaid amount after partial payments.

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Cash flow

Cash in and out over time—not the same as profit.

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Credit memo

Negative invoice that reduces what a customer owes.

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Dunning

Structured process for overdue invoice follow-up.

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Invoice aging

Buckets of receivables by days past due.

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Late fee

Charge or interest for paying after the due date.

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Payment processor

Service that moves card/ACH money to your bank.

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Payment terms

When and how invoice amounts must be paid.

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Purchase order (PO)

Buyer authorization that caps what you can bill.

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Quote vs invoice

Estimate vs request for payment after delivery.

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Remittance advice

Note that explains which invoices a payment covers.

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Retainage

Held-back percentage until construction work closes.

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Sales tax

Transaction tax on taxable sales in a jurisdiction.

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VAT

Value-added tax common outside the US.

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Withholding tax

Tax withheld from a payment and remitted for you.

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Write-off

Remove uncollectible AR from books per policy.

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Early payment discount

Reduced price for paying before the due date.

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Chargeback

Card payment reversal after a customer dispute.

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Apply what you learn

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