Weitere Info´s auf der isländischen Zoll-Seite, englisch:VAT Refund
Value Added Tax refund
Value Added Tax (VAT) may be refunded to persons resident abroad on goods that they have purchased in this country, subject to the conditions of regulations.
The condition of a tax refund according to this regulation is that the buyer of the goods is a permanent resident of a country other than Iceland. As proof of permanent residence the buyer shall show a passport, a certificate of residence from the Icelandic Statistical Bureau, or other documents that unequivocally prove permanent residence in another country. Foreigners with permanent residence in Iceland do not have the right to a refund in accordance with this regulation.
In order to obtain a refund, all of the following conditions must be met:
The buyer will bring the goods out of the country within three months of the purchase.
The purchase price of the goods with VAT is a minimum of ISK 4,000.
The articles along with required documents are produced at departure.
VAT may be refunded of goods on the same receipt if their total value is ISK 4,000 or more including VAT, even though one or more items does not reach the required minimum value.
On departure from the country through Keflavik International Airport, the buyer shall produce the articles along with a refund cheque to the refund service provider, who will purchase it subject to the fulfilment of all the conditions of this regulation. The refund provider may not purchase the cheque unless the buyer supplies sufficient proof that s/he is a permanent resident abroad. If the amount of the refund exceeds ISK 5000, the customs authorities shall confirm the export of the goods with a signature on the cheque.
The National Bank of Iceland in Leifur Eiriksson Terminal is responsible for refunding VAT. The bank is located on the second floor after passing through weapons control in Customs.
http://www.customs.is/displayer.asp?cat_id=302
In Keflavik Airport the office is just after the check-in table, across the hall from the cafeteria.
In Seyðisfjörður the main office is the ferry terminal.
For sailboats, cruise ships, private aircrafts and other vessels customs officers arrive on board for the customs clearance before departure, according to appointments made by the vessels captain.
