# Invoices The invoice represents the business transaction between you and your customer. In Resolve, an invoice must be tied to a customer and an advance can be taken on the invoice. For an advance to be taken on the invoice, a PDF of the invoice must be uploaded and the associated customer must be approved and have available credit for the amount of the invoice. ## List all invoices - [GET /invoices](https://resolve.redocly.app/swagger/invoices/listinvoices.md): Return a list of invoices. ## Create an invoice - [POST /invoices](https://resolve.redocly.app/swagger/invoices/createinvoice.md): Create a new advanced or non-advanced invoice with the desired terms. ## Fetch an invoice - [GET /invoices/{invoice_id}](https://resolve.redocly.app/swagger/invoices/fetchinvoice.md): Retrieve an existing invoice by its ID. ## Update an invoice - [PUT /invoices/{invoice_id}](https://resolve.redocly.app/swagger/invoices/updateinvoice.md): Update an invoice. ## Delete an invoice - [DELETE /invoices/{invoice_id}](https://resolve.redocly.app/swagger/invoices/deleteinvoice.md): Delete an invoice. ## Send an invoice - [PUT /invoices/{invoice_id}/send](https://resolve.redocly.app/swagger/invoices/sendinvoice.md): Send an invoice to the customer. ## Void an invoice - [POST /invoices/{invoice_id}/void](https://resolve.redocly.app/swagger/invoices/voidinvoice.md): Void an invoice. ## Cancel an invoice - [POST /invoices/{invoice_id}/cancel](https://resolve.redocly.app/swagger/invoices/cancelinvoice.md): Cancel an invoice.