To receive back a portion of the tax paid on purchases made in Britain, first ask the store personnel if they do VAT refunds and what their minimum purchase is. Once you've achieved this minimum, ask for the paperwork; the retailer will have to fill out a portion themselves. Several readers have reported that merchants have told them that they can get refund forms at the airport on their way out of the country. This is not true. You must get a refund form from the retailer (don't leave the store without one), and it must be completed by the retailer on the spot.

Fill out your portion of the form and present it, along with the goods, at the Customs office in the airport. Allow a half-hour to stand in line. Remember: You're required to show the goods at your time of departure, so don't pack them in your luggage and check it; put them in your carry-on instead.

Once you have the paperwork stamped by the officials, you have two choices: You can mail the papers and receive your refund in either a British check (no!) or a credit-card refund (yes!), or you can go directly to the Cash VAT Refund desk at the airport and get your refund in your hand, in cash. The bad news: If you accept cash other than sterling, you will lose money on the conversion rate. (If you plan on mailing your paperwork, try to remember to bring a stamp with you to the airport; if you forget, you can usually get stamps from stamp machines and/or the convenience stores in the terminal.)

Be advised that many stores charge a flat fee for processing your refund, so £3 to £5 may be automatically deducted from the refund you receive. But because the VAT in Britain is 17.5%, if you get back 15%, you're doing fine.

Note: If traveling to other countries within the European Union, you don't go through any of this in Britain. At your final destination, prior to departure from the European Union, you file for all your VAT refunds at one time.