Invoicing and small-business glossary

Plain-English definitions of the invoicing, payment, tax, and bookkeeping terms service-business owners run into — net 30, retainage, markup vs margin, 1099-NEC, and more.

• Invoice
• Estimate
• Quote
• Receipt
• Proforma invoice
• Credit note
• Debit note
• Invoice number
• Purchase order (PO)
• Billable hours
• Line item
• Subtotal
• Deposit
• Retainage
• Progress billing
• Milestone billing
• Recurring invoice
• Void invoice
• Past due
• Aging report
• Accounts receivable (AR)
• Accounts payable (AP)
• Billing cycle
• Scope of work
• Change order
• Trip fee
• Service call fee
• Diagnostic fee
• Minimum charge
• Flat-rate pricing
• Time & materials (T&M)
• Markup
• Gross margin
• Deposit invoice
• Final invoice
• Net 30
• Payment terms
• Due on receipt
• Late fee
• ACH transfer
• Wire transfer
• Card payment
• Tap to Pay
• Stripe
• Payment link
• Convenience fee
• Refund
• Chargeback
• Deposit account
• Settlement
• Interchange fee
• KYC / KYB
• Payout
• Partial payment
• Payment plan
• Sales tax
• Use tax
• Tax nexus
• Exemption certificate
• 1099-NEC / 1099-MISC