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Invoicing OPG

Are you a valued Ontario Power Generation supplier or partner looking to invoice? Discover everything that's required to submit your invoice to us.

OPG and Ariba

For consistency and transparency, all OPG vendors submitting invoices to OPG are required to use the Ariba network.

If you require help submitting your invoice using Ariba, please contact [email protected].

Evaluated receipt settlement (no invoice required)

For evaluated receipt settlement (ERS) purchase orders, do not submit invoices against this PO.

OPG will automatically create a payment invoice upon receipt of material against an OPG purchase order. Payment amounts are based on the prices contained within the purchase order.

Invoicing information

Invoices are reviewed for compliance with purchase order terms and conditions before payment. Per OPG policy, calculation of the payment date is dictated by terms laid out in the purchase order.

Payment will be withheld for any non-conformance issues until such time that the issue is resolved.

Material goods received into inventory require acceptance approval prior to release of payment.

Calculation of the payment date is determined by the terms laid out in the purchase order.

Payment terms are: Pay on the 25th of the month, which is calculated based on invoice date and upon acceptance of goods unless stated otherwise in the purchase order.

We encourage all Canadian and U.S. vendors to sign up for electronic payments (EFT/ACH) and electronic remittances.

An invoice may be rejected and returned for any of the following reasons:

  • The invoice is not addressed to Ontario Power Generation Inc.
  • Does not contain any of the following:
    • OPG PO number and release number, where applicable
    • A unique invoice number
    • Invoice date
    • Supplier name as stated in the PO
    • Remittance address
    • PO Line item number and quantity, description (including Catalogue ID number or Material Code) and unit price of goods/services (as stated in the PO): for service POs, must include contractor’s name, hourly labour rate, and detailed breakdown of hours worked and billing period
    • Total invoice amount
    • Currency
    • GST registration, and if charging, GST
    • Shipping terms and required documentation
    • Other substantiating documentation as noted in the PO
  • The approver will not approve the invoice if work is not done to contract satisfaction or the work was unauthorized.
  • The amount being billed is in excess of the amount on the purchase order, in terms of price, hours, rates, or total purchase order value.

It is our policy not to short pay (provide partial payment) on invoices. However, OPG will make regulatory adjustments to invoices that will result in short payment, including:

  • Withholding tax was collected (applies to foreign vendors providing services in Canada).
  • Amount has been held back in accordance with the terms and conditions of the purchase order, i.e., holdback contracts.

The Income Tax Act generally requires that every person making a payment to a non-resident person (including individuals and corporations) withholds income tax on the payment. This includes payment to non-residents for services performed in Canada, rents, royalties and similar amounts.

OPG is required to withhold 15% tax on payments made to non-residents for services of any kind performed in Canada, regardless of the currency in which the invoice is rendered. The tax is remitted to Canada Revenue Agency (CRA) on the non-resident's behalf. This amount withheld may only be reduced or waived by Canada Revenue Agency (CRA).

Annually, T4A-NR supplementary tax documents are prepared for each non-resident identifying the amount of tax withheld for the prior calendar year.

OPG is required to withhold tax on payments made to non-residents for rents, royalties and similar amounts paid or credited, regardless of the currency in which the invoice is rendered. The tax applies to all payments whether they are single, lump-sum or periodic. The tax is remitted to Canada Revenue Agency (CRA) on the non-resident's behalf, monthly on the 15th day of the calendar month following the calendar month in which the non-resident is paid.

The tax withheld on rents, royalties and similar amounts is generally 25% but may be reduced by tax treaties that Canada has with various countries depending on the type of payment and country to which the payment is made (e.g. 10% for the United States).

Rents, royalties or similar payments include amounts paid for:

  • The use of or the right to use in Canada any property, invention, trade-name, patent, plan, design or model, secret formula, process or trade-mark know-how, i.e., information concerning industrial, scientific, or commercial experience where the payment depends partially or wholly on the use to be made or benefit derived from the information; on profits; or on production or sales of goods or services.
  • Technical services, i.e., services of an industrial, commercial or scientific character where the payment depends partially or wholly on the use to be made or benefit derived from the services; on profits; or on production or sales of goods or services. Note: Payments for technical services performed in connection with the sale of property or negotiation of a contract are excluded and not subject to withholding tax.

Failure to withhold, remit and report the required withholdings, where applicable, will result in a tax liability to OPG, plus interest and penalties, thereby increasing OPG’s costs if there is a failure to correctly identify the application of withholding tax at the beginning of the contract.