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Purchase Order Number

When invoicing for goods or services, suppliers must quote a valid Purchase Order (PO number) on the invoice, in order to receive payment.

To help improve efficiency in our payment processes and ensure that all payments are made to suppliers as quickly as possible, suppliers must ensure that they are provided with a PO number when accepting an order for goods or services.

Any invoice received without a valid PO number will result in delays as it will not be processed and will be returned to the supplier unpaid.

I never quoted a PO number on my invoice and still got paid. Can I not continue to do this?

No. We implemented the No PO No PAY policy to ensure all financial commitments are approved and recorded in purchasing systems in advance of the purchase being made.

Are any goods and services exempt?

Exemptions usually only apply to:

  • Utilities
  • Rate refunds
  • Council tax
  • Grant payments

For low value and/or one off purchases, we use purchase cards (P-cards).If you have received a card number to process the payment against, then a PO number will not be required.

If you are submitting an invoice in a foreign currency, you are not required to provide a PO. This type of invoice should be sent directly to the City of London contact who commissioned the work.

Will I get paid any quicker if I provide a PO number?

No. However, invoices without a valid PO number will not be processed or paid until a valid PO number is quoted by the supplier and this will delay your payment.

The standard payment terms the City Corporation adheres to are:

  • 10 days for small to medium enterprises
  • 30 days for large companies
  • immediate for non-trade

What does a valid PO number look like?

A valid PO number from The City Corporation will begin with a number seven and will have six digits: eg 712345.

Where can I get a PO number from?

  1. Get a valid PO number from your contact within the City Corporation who provided you with an instruction for the goods/service.
  2. Enter the PO number on your invoice
  3. Submit the invoice to the City of London Corporation Accounts Payable Team

My contact details have changed. Who do I contact to get these corrected?

If you need to let us know of any changes contact the City Procurement Projects or email the Accounts Payable team.

Please note: Due to the requirements of the Data Protection Act 1998, we need to record your formal authorisation to amend your records. We ask that all changes be confirmed in writing - email accepted - to maintain compliance and meet with audit requirements.

If you are currently paid by cheque we would encourage you to provide us with your current bank account details in writing so that we are able to improve the efficiency of your payment.

More information

If you have any further questions regarding the No PO No PAY policy contact City Procurement or email the Accounts Payable team.