Purchase orders, proformas and commercial invoices
A purchase order records what the buyer orders; a proforma sets out the supplier's offer and payment request; a commercial invoice records the goods supplied for customs paperwork. Reconcile the agreed terms, actual shipment and payments rather than treating the documents as interchangeable. Ask Cambridge China Bridge to review discrepancies before paying.
Give each document a clear job
Use the purchase order to communicate your order, the proforma to check the supplier's offer before payment, and the commercial invoice to document the actual consignment. Keep their references connected so purchasing, accounts and the customs broker can trace the same transaction.
These documents may arrive in a different sequence. A supplier might send a proforma before you issue your purchase order. Compare them and ask for written agreement on differences before authorising production or payment.
| Document | Usually prepared by | When to issue or update | Main purpose |
|---|---|---|---|
| Purchase order | Buyer | When placing the order; revise when agreed order terms change | Record the goods and terms the buyer is ordering |
| Proforma invoice | Supplier | When presenting the offer or requesting advance payment; revise if the offer changes | Set out the proposed supply and payment request |
| Commercial invoice | Supplier | When shipment details are confirmed, before sending the paperwork to the broker | Record the goods supplied and their invoiced value |
Agree the order before paying
Give the purchase order a reference and identify the specification revision, approved sample, quantities, currency, delivery terms and payment conditions. Ask the supplier to acknowledge it and reference it on the proforma. For the detailed field checks, use our proforma invoice guide.
If the proforma changes a material, quantity, delivery term or inspection condition, resolve that difference explicitly. Ask both parties to identify the agreed documents and revisions in writing. Avoid leaving purchasing with an earlier order while accounts pays against a changed offer.
Separate shipment value from money still owed
Ask for the commercial invoice to show the goods in the actual shipment and their full agreed invoiced value. Show advance payments and the remaining balance separately in the payment reconciliation, rather than presenting the balance alone as the goods' value. Give the broker any separate freight, insurance, tooling or other charges to assess.
For a split shipment, map each shipped line back to the order and record what remains unshipped. Agree how the deposit is allocated and check that it is not deducted again on later payment requests. Before releasing the balance, follow our pre-payment checks.
Check the document set before dispatch
Compare seller and buyer identities, order references, product descriptions, shipped quantities, unit prices, totals, currency and delivery terms. Match the commercial invoice to the packing list and transport document. Explain differences caused by a partial shipment or an agreed change; do not alter documents merely to make them look identical.
Send the reconciled set to the broker before dispatch and flag unresolved items. Our customs document guide covers the individual documents and supporting paperwork. HMRC says proformas should be clearly identified as such and preferably marked as not being VAT invoices; keep that distinction when sharing files.
Revise documents without losing the trail
When the order changes, revise the purchase order and ask for an updated proforma reflecting the agreed change. When the actual shipment differs, ask the supplier for a commercial invoice that reflects it. Give revised documents a clear date or revision reference, identify what they supersede and retain the earlier versions with the approval correspondence.
If an invoice error is discovered after documents have reached the broker, send the correction and explanation to the broker and accounts together. Ask whether the declaration also needs correction. Avoid silently replacing a file or backdating it. Keep payment confirmations linked to the order so a replacement invoice does not trigger duplicate payment.
Frequently asked questions
Do I need a purchase order if I have a proforma?
A purchase order helps record your specification and approval conditions. If you order against a proforma, attach those details and obtain written agreement before paying.
Should the commercial invoice show only the balance?
Ask for the full agreed invoiced value of the shipped goods, with advance payments and the balance reconciled separately. Give the broker the complete payment and charge details.
Must the purchase order and commercial invoice match?
The agreed terms should reconcile, but a partial shipment may have different quantities and totals. Link the shipped lines to the order and record the quantities still outstanding.
What if the supplier changes the invoice after payment?
Ask what changed and why. Retain both versions, obtain written agreement on commercial changes and notify accounts and the broker if they already hold the earlier document.