Adding a customization should prompt a review of the payment terms, not an automatic price increase, deposit, or reset of the payment schedule. The revised pro forma invoice should state either that the existing terms remain unchanged or explain exactly how they will change. A customization alone does not establish how much a payment term should change.
The U.S. International Trade Administration notes that a pro forma invoice can include payment terms. It also says changes to future-shipment details should not be made without the buyer’s consent. However, the cited guidance does not state that customization automatically changes payment terms or prescribe a universal adjustment formula.
What should the revised quote make clear?
The buyer should compare the original quote with the revised pro forma invoice and check the following:
| Review point | Question for the buyer |
|---|---|
| Customization scope | What exactly is being added, and which existing items or services remain excluded? |
| Payment amount | Does the total change? If so, what is the exact revised amount? |
| Payment timing | Do the existing dates, payment sequence, or conditions remain in place? |
| Revised terms | If anything changes, does the document state the new terms clearly rather than merely referring to a separate agreement? |
| Future-shipment details | Which shipment details are changing, and has the buyer consented to those changes? |
| Cancellation or refund consequences | What happens if the customized order is canceled or the quotation expires? |
These questions help separate the added customization from any proposed change to the commercial terms. They also prevent a revised shipment schedule from being mistaken for permission to revise payment terms.
Is an additional deposit or shorter deadline required?
The cited guidance does not say that adding a customization automatically requires an additional deposit, full prepayment, a shorter payment deadline, staged payments, or a particular price increase. It therefore supports no fixed percentage, deadline, or repricing rule.
The buyer should not assume that any of these changes applies. If payment terms are revised, the pro forma invoice should identify the applicable amount, timing, and conditions. If they are unchanged, saying so explicitly can prevent later uncertainty.
What must the buyer confirm separately?
The buyer remains responsible for confirming matters that the cited guidance does not resolve. In particular, the buyer should obtain direct written answers about:
- the full scope and exclusions associated with the customization;
- any change to the quoted amount;
- the applicable payment dates, sequence, and conditions;
- every proposed change to future-shipment details;
- any refund, cancellation, or expiration provisions; and
- whether the revised pro forma invoice replaces the earlier version in full or only in part.
A revised pro forma invoice should make any change—or lack of change—explicit. Where it is silent, the buyer should ask rather than infer terms from the customization itself.