# USPS can now invoice US mailers for unpaid destination customs charges

> An interim rule effective 19 October 2026 lets USPS bill mailers for foreign customs charges reported unpaid at destination. Sellers remain liable even when disputing or when parcels fail, and the sources do not say which of USPS's 18 DDP destinations require prepayment.

- Publication: The Sourcing Herald
- URL: https://sourcingherald.com/articles/usps-can-now-invoice-us-mailers-for-unpaid-destination-customs-charges
- Format: News
- Section: Business Guides
- Published: 2026-10-28
- Sources last checked: 2026-10-26

## Key points

- USPS can now invoice US mailers when a destination customs charge is reported unpaid, under an interim final rule effective 19 October 2026 [1][2].
- Merchants must pay the USPS invoice even while disputing it, and the charge remains due if a parcel is delivered, lost, damaged or returned [1].
- Past-due USPS customs invoices accrue interest at 6% annually, according to Practical Ecommerce [1].
- USPS's prepaid import duties page lists 18 eligible DDP destinations, but the sources do not say which require DDP [3].

The United States Postal Service (USPS) can now bill US mailers for certain foreign customs charges that are reported unpaid at destination. An interim final rule, *Customs Requirements and Payment Procedures for Certain Customs Charges*, was published in the Federal Register on 19 October 2026 and took effect the same day [2]. USPS's Delivered Duty Paid (DDP) service lets a sender prepay those charges, and USPS's prepaid import duties page lists 18 eligible destinations [3]. The sources do not say which of those destinations require DDP, so sellers should check each destination before shipping.

## USPS can now invoice US mailers for unpaid destination duties

USPS has revised its International Mail Manual (IMM) to update mailer responsibilities for customs requirements and to set procedures for paying, or reimbursing, customs charges, including charges assessed after postage is bought [2]. Under the rule, USPS, directly or through a third-party representative, will invoice the shipper, called the "mailer" in postal terms, when a customs agency, postal operator, broker or other service provider reports a charge as unpaid [1]. Practical Ecommerce reported the rule on 25 October 2026 [1].

Not every US merchant sending abroad will receive a bill. Responsibility for customs charges depends on the destination country's requirements and the shipping method [1].

## Who is affected and what changes for sellers

US mailers that ship international parcels through USPS are exposed when a destination charge is reported unpaid. Practical Ecommerce says the change applies to all countries and regions, not only the European Union, and that all carriers, including UPS and FedEx, must ensure those charges are paid [1]. Switching carriers therefore does not remove the underlying risk [1].

The rule creates three cost risks for sellers:

- **Disputes do not pause payment.** The merchant must pay the USPS invoice even while disputing an incorrect assessment, and must pursue the dispute with the entity that made it [1].
- **Failed deliveries do not remove the charge.** The shipper remains responsible for applicable charges whether the parcel is delivered, lost, damaged or returned [1].
- **Late payment costs more.** A past-due USPS invoice accrues interest at 6% annually [1].

Practical Ecommerce gives an example of a $100 order to France [1]. The customer declines the package because of an unexpected customs charge, and the merchant refunds the order when the product comes back. The merchant could still owe the unpaid customs charge, with interest [1].

## The EU change behind the rule

The rule follows a change in the EU. As of 1 July 2026, the European Commission eliminated the de minimis exemption for most low-value goods destined for the EU customs territory [2]. Under the EU's temporary arrangement, each unique Harmonized System (HS) product code carries a flat, non-refundable €3 duty [3]. A parcel with three items in the same HS classification pays €3 in total, and a parcel with two classifications pays €6 [1]. For more on that duty, see our [EU €3 parcel duty explainer](/articles/eu-3-euro-parcel-duty-how-it-is-counted-and-what-it-does-to-landed-cost) [1].

## How prepayment and DDP work

USPS says that, depending on the destination, prepaying duties, taxes and fees may be required to buy postage, and it recommends prepayment to help streamline customs screening and prevent delays [3]. If the duties are not prepaid, the recipient must pay the required amounts before receiving the package [3]. With DDP, a merchant obtains a quote and prepays applicable duties, taxes and fees when purchasing postage [1]. USPS does not charge for DDP, but its third-party provider, Zonos, includes a fee in the quote [1], and the DDP quote is not an absolute ceiling [1].

USPS systems that integrate DDP are retail service counters, Click-N-Ship, certain USPS APIs and Global Shipping Software (GSS), and these systems automatically calculate import duties, taxes and fees [3]. Customs descriptions must be detailed and accurate, because USPS uses them to assign HS codes [3]. If the customs form is not completed correctly, mail may be delayed, or duty and taxes could be incorrect [4].

A USPS Help Center article on customs forms, retrieved on 26 October 2026, states that destination-country duties "can NOT be paid to the United States Postal Service® when the item is mailed" and that "the recipient must pay customs fees" [4]. The sources do not say whether that article has been updated to match the new rule.

## Which destinations are on USPS's DDP list?

USPS's prepaid import duties page lists 18 eligible destinations for DDP: Austria, Belgium, Canada, Denmark, Estonia, Finland, France and Territories, Germany, Italy, Luxembourg, Malta, Monaco, the Netherlands, Portugal, Slovakia, Spain, Sweden and the United Kingdom [3]. The France entry includes Guadeloupe, French Guiana, Martinique, Andorra, Réunion and Mayotte [3]. USPS says DDP works when shipping by Priority Mail Express International, Priority Mail International and First-Class Package International Service, and that more countries are expected to be added [3].

The sources do not say which of these destinations require DDP, and they do not give a country-by-country requirement list. Some EU postal operators require certain items to be sent using an approved DDP solution, under which the mailer pays duties, taxes and import fees [2]. For EU shipments to countries not accepting DDP, USPS says duties, taxes and fees are handled on a country-by-country basis [3].

## What sellers should do now

- **Map your destinations.** List every country you ship to, and mark which ones appear on USPS's 18-destination list [3].
- **Check the rest individually.** For each destination not on the list, check the country's listing in the IMM before shipping [4].
- **Check your shipping system.** Confirm that Click-N-Ship, a retail counter, an API or GSS shows the duty calculation and prepayment option for each international label [3].
- **Write detailed item descriptions.** USPS uses them to assign HS codes, so vague descriptions can produce the wrong code [3].
- **Keep prepayment records.** Keep the prepayment record with each shipment, so that any later USPS invoice can be matched to a specific parcel. This is our advice, not a USPS requirement.
- **Check the USPS page regularly.** USPS says more countries are expected to be added [3].

## What is not yet known

- **The full DDP requirement list.** The sources do not say which listed destinations require DDP or give a country-by-country requirement list. Check USPS's prepaid import duties page for the current position. We reviewed it on 26 October 2026.
- **How invoices will arrive.** The rule itself does not specify how invoices will be sent [1].
- **Next countries and dates.** USPS says more countries are expected to be added, but the sources do not name them or give a date [3].
- **Whether the customs FAQ has been updated.** The sources do not say whether the USPS customs forms article has been revised to match the new rule [4].
- **Whether the rule will change.** Comments must be received by 18 November 2026 [2]. The sources do not say whether the rule will change after that date.

## Frequently asked questions

### When did the USPS customs charges rule take effect?

The interim final rule was published in the Federal Register on 19 October 2026 and took effect the same day [2].

### Does switching to UPS or FedEx avoid this risk?

No. Practical Ecommerce says all carriers, including UPS and FedEx, must ensure those charges are paid, so switching carriers does not remove the underlying risk [1].

### What happens if a customer refuses a parcel with a customs charge?

The shipper remains responsible for applicable charges whether the parcel is delivered, lost, damaged or returned, so a refund to the customer does not necessarily cancel the charge [1].

### Which destinations are on USPS's DDP list?

USPS lists 18 eligible destinations, including Austria, Germany, France and the United Kingdom, and says more countries are expected to be added [3].

## Sources

1. USPS Can Bill Sellers for Foreign Duties — Practical Ecommerce (Armando Roggio), published 2026-10-25. https://www.practicalecommerce.com/usps-can-bill-sellers-for-foreign-duties
2. Federal Register Notices (USPS Mailing Standards Department index) — United States Postal Service (Postal Explorer), published 2026-10-19. https://pe.usps.com/FederalRegisterNotice/Index
3. Import Duties | USPS (Prepaid Import Duties, USPS Delivered Duty Paid) — USPS. https://www.usps.com/international/prepaid-import-duties.htm
4. Customs Forms: The Basics (USPS FAQ) — USPS Help Center. https://faq.usps.com/articles/Knowledge/Customs-Forms-The-Basics