If an article is made in the United States, subsequently exported, and then returned to the US, without having been "advanced in value or improved in condition" by any process of manufacture or other means while out of the country, it is not subject to duty upon its return to the United States (Harmonized Tariff Classification 9801.00.10).

To many importers, this appears to be one of the simplest tariff provisions with which to deal. These may be relatively painless import transactions, however many times these transactions turn out to be quite difficult and troublesome. A common error is that all articles exported and then returned are duty free; this is not the always the case. US Customs & Border Protection (CBP) is concerned with physical changes to articles that improve them. Therefore, a foreign shipper must be certain the articles qualify as US Goods Returned. False declarations are violations of Customs law.

Foreign shippers may be able to state that the articles were originally exported from the United States, but not that they were in fact made in the United States. If you claim "free" entry because the goods were made in the United States, be prepared to prove it.

Foreign shippers should provide proof that an article was made in the United States by obtaining a Manufacturer's Affidavit.

The affidavit is relatively simple to obtain if the importer is also the manufacturer of the article. However, in many instances the importer purchased the article domestically from someone else. They will then have to contact the actual producer of the article and request affidavits from that company. If a variety of articles are imported this could be a burdensome and costly undertaking. Foreign shippers are advised to review the requirements for shipping US Goods Returned, with their Customs Broker prior to shipment.