Advance payment
Money received before the work is done. In the books it is not income but a liability — the work is still owed.
More terms under Invoicing, payment and banking: Allowance for doubtful debts Bad debt camt.053 Cancellation invoice Cash discount Certificate of shortfall Credit note Creditor Current account Debt enforcement Debtor Default interest Delivery note Dunning eBill Final invoice IBAN Invoice number ISO 20022 / camt Open items pain.001 Part payment Payment term Pro forma invoice QR reference QR-bill QR-IBAN Quotation Receipt Tips TWINT as a payment method Visitor taxes