The simple version

When a parcel reaches another country, that country may levy a charge on it. Someone has to settle that, and most people assume it falls on the person who opens the box.

The new procedures say otherwise for a lot of outbound mail. The mailer carries it, and the Postal Service can bill the mailer for amounts it has already covered.

And it does not depend on the parcel arriving. The document says the mailer still carries the amount whether the parcel turns up, goes missing, or comes back.

The numbers

• United States Postal Service final rule, Customs Requirements and Payment Procedures for Certain Customs Charges, revising Mailing Standards of the United States Postal Service, International Mail Manual, 39 CFR part 20, citation 91 FR 66000, published and effective October 19, 2026 (Federal Register document 2026-21310)
• Comments on the rule must be received by November 18, 2026 (same document, DATES)
• The stated purpose is to update mailer responsibilities with respect to customs requirements and to establish procedures for the payment, or reimbursement, of any customs charges that are assessed (same document, summary)
• The document states that the changes respond to European Union customs rules that took effect July 1, 2026 (same document, summary)
• The document states that whether the mailer or addressee is responsible for paying duties, taxes and import fees depends on various factors including, but not limited to, the customs requirements of the destination country (same document)
• The document states that where a destination customs authority or postal operator seeks to collect duties, taxes or import fees from the mailer or the Postal Service and those amounts have not been paid in full, the mailer is responsible for paying, or in certain circumstances reimbursing the Postal Service for, such amounts (same document)
• The document gives one example: when an item is sent on a delivered duty unpaid basis and the amounts cannot be recovered from the addressee, the destination postal operator may seek to collect them from the mailer (same document)
• The document states that the mailer must pay the Postal Service, or its representative, the entire amount due (same document)
• The document states that the mailer is not relieved of its obligation to pay duties, taxes and import fees (same document)
• Where amounts remain outstanding, the document states that the Postal Service or its representative will send an invoice to the mailer for those amounts (same document)
• The document states that if payment is not received on or before the due date set forth in the invoice, interest on the unpaid amounts will accrue at a rate of 6 percent per annum until the amounts are paid in full (same document)
• The document states that the mailer is not relieved of its obligation to pay duties, taxes and import fees regardless of whether the item is delivered, lost, damaged, or returned (same document)
• The stated purpose includes establishing procedures for the payment, or reimbursement, of any customs charges that are assessed, including after the purchase of postage (same document, summary)

Why the charge lands on the person sending

Follow the order of events and it makes sense. The destination country assesses its charge after the item has left the United States, so nobody on this side is standing there to collect it.

The Postal Service or its agent often settles that charge so the item keeps moving. Having paid, it then needs someone to recover from.

The recoverable party is the one who entered into the mailing and signed the label, which is the mailer. The person waiting for the parcel never signed anything.

That is also why the interest line exists. The arrangement is money owed rather than money exchanged, and anything owed carries a cost of waiting.

The actual math the rule does set

One rate is published and nothing else is. If payment is not received by the due date on the bill, interest runs on the outstanding amount at six percent per annum until it is cleared.

That is the only figure in this article, and it is a rate rather than an amount. The charge itself is set by the destination country, not by this document, so no total can be worked out here.

The start point matters as much as the rate. Interest runs from the due date on the bill rather than from the day the charge arose, so the clock depends on when the bill is issued.

The rule is also still open for comment, which means it is in force and capable of changing at the same time.

What this means

The habit worth building is to treat the label as a document rather than a formality. What is written there about contents and value is what any later charge gets calculated from.

It is also worth separating two questions that get blurred. Who the destination country assesses is one thing, and who the Postal Service can recover from afterwards is another.

And the broader read applies well beyond mail. When someone fronts a payment on your behalf to keep a process moving, you have borrowed from them, whether or not it was ever called borrowing.

What this is NOT

This article explains where the obligation for a border charge sits under the Postal Service's new procedures, using the final rule Customs Requirements and Payment Procedures for Certain Customs Charges, 39 CFR part 20, citation 91 FR 66000, published and effective October 19, 2026, read on October 19, 2026. It is not advice about whether or how to send anything, it recommends no carrier, service or declaration method, and it is not guidance on completing any form. It states no amount for any charge, because the charge is set by the destination country and this document does not set one: the single rate given here, six percent per annum running from the due date on the bill, is the document's own and nothing is computed from it. It is not a guide to the customs law of any country, including the European Union rules the document says prompted the change, none of which this article describes. It does not cover tariffs on commercial imports into the United States, which are a different subject with their own pages. It is not legal or tax advice, and it makes no claim about anyone's liability in any particular shipment. It is not a complete account of the International Mail Manual. It does not name the official who signed the document or the staff listed as contacts. This is not a political endorsement or criticism of anyone.

Sources

• United States Postal Service, Customs Requirements and Payment Procedures for Certain Customs Charges, final rule, 39 CFR part 20, citation 91 FR 66000, published and effective October 19, 2026, read October 19, 2026: https://www.federalregister.gov/documents/2026/10/19/2026-21310/customs-requirements-and-payment-procedures-for-certain-customs-charges