XII. Expenditures

Guide to Financial Operations

XII.5.B Unique Invoice Number Requirements

XII. Expenditures
Guide to Financial Operations


The Statewide Financial System (SFS) requires Business Units to enter a unique Invoice Number on each supplier’s voucher. The SFS has validations that will help prevent Business Units from processing and paying duplicate invoices. With few exceptions, as described later in this section, Business Units should use the invoice number on a vendor’s invoice to process the voucher.

Business Units must include only one invoice on a voucher to facilitate the SFS functionality that prevents the payment of duplicate invoices.

Process and Transaction Preparation:

When a Business Unit must create more than one voucher to pay the same invoice, the Business Unit must have a process to ensure that each voucher (1) references a unique invoice number and (2) includes only items it has received and not paid for on a previous voucher. Business Units may encounter this situation when making a partial payment due to a partial delivery. Partial payments should rarely occur because Business Units should request that vendors invoice for goods or services that have been delivered.

For example, assume a Business Unit wants to make a partial payment against invoice number 123 due to a partial delivery. The Business Unit can enter invoice number 123 into the Invoice Number field to create a voucher to make a partial payment. The Business Unit should make it clear on the voucher the portion of the invoice for which payment is being made. When the Business Unit receives the remaining goods on invoice number 123, it can create a second voucher with invoice number 123-2 in the Invoice Number field to make the second payment.

In certain circumstances, a vendor may be unable to provide a unique invoice number or the vendor’s invoice may not include an invoice number. Business Units are responsible for determining, documenting and applying a consistent method to use unique invoice numbers and may need to contact their vendors to agree to an acceptable method.

Business Units must include only one invoice on a voucher. Combining invoice numbers in the Invoice Number field on a voucher may cause the following problems:

  • The SFS will not automatically prevent the payment of duplicate invoices
  • Vendors may not accurately credit Business Units for payments.
  • Vendors may not be able to reconcile the invoice numbers and payments on e-Supplier with invoice numbers, payments and accounts in their systems.
  • Business Units may have difficulty identifying an overpayment of a single invoice to a vendor.


The Office of the State Comptroller has worked with certain complex vendors, such as National Grid and Verizon, to develop a consistent invoice numbering method for Business Units to use to ensure each payment request has a unique invoice number that satisfies the processing needs for New York State and the vendor. Business Units should refer to Section 6.Z – Processing Payment to Complex Entities of this Chapter, for more information about how to generate or reference unique invoice numbers and process payments to complex vendors.

Online Business Units

Paper Invoices

When a Business Unit enters a duplicate invoice number on a voucher, the SFS displays a warning message and the Business Unit is unable to continue processing the voucher until it enters a unique invoice number.

Electronic Invoices

When a vendor submits an electronic invoice with an invoice number that has already been processed by a Business Unit to the vendor in the Accounts Payable module, the electronic invoice is automatically rejected back to the vendor. Business Units should refer to Section 4.E – Electronic Invoicing Process of this Chapter, for more information about electronic invoices rejected back to vendors.

Bulkload Business Units

When a Business Unit submits a voucher to the SFS using a duplicate invoice number, the SFS rejects the voucher.

Bulkload Business Units cannot currently receive electronic invoices via the SFS.

Guide to Financial Operations

REV. 04/02/2015