I've been meaning to blog this wee tip for ages and finally got round to it today. When shipping parcels from the UK to the USA the standard zip code is something like AB 12345. However, I've stumbled across the USPS zip code look up site which allows you to enter the address and zip code. It then gives you an additional 4 numbers for the end of the zip code, which should help speed up the delivery of your parcel.
All good with the (fingers crossed) christmas rush just around the corner!