If an employee relocates to the USA for a short period of time and ships their belongings from their home to their new residence in the US, are there any duties that need to be paid ?
Yes. (Generally speaking.)
Import duty and taxes are due when importing goods into the United States whether by a private individual or a commercial entity. The valuation method is FOB (Free on Board), which means that the import duty and taxes payable are calculated exclusively on the value of the imported goods. However, some duties are based part in value and part in quantity. In addition to duty, imports may be subject to a Merchandise Processing Fee, and in some cases to sales tax, and Federal Excise Tax.
Here is the official page of U.S. Customs. They write:
Household Effects & Personal Effects - Customs Duty Guidance
Household effects conditionally included are duty-free. These include such items as furniture, carpets, paintings, tableware, stereos, linens, and similar household furnishings; tools of the trade, professional books, implements, and instruments.
You may import household effects you acquired abroad duty-free if:
- You used them abroad for no less than one year.
- They are not intended for any other person or for sale.
For Customs purposes, clothing, jewelry, photography equipment, portable radios, and vehicles are considered personal effects and cannot be brought in duty-free as household effects. However, duty is usually waived on personal effects more than one year of age. All vehicles are dutiable.