Do you need to send mail to the United Kingdom? You might have everything but the postcode. Just as ZIP codes operate in the United States, having the postcode on any piece of mail bound for the United Kingdom will help avoid complications during processing and delivery. If you're having trouble remembering that particular bit of information, here's how you can find it.
Try going to thephonebook.bt.com or another U.K. phone book site first. If the addressee is listed, this will provide the complete address information, including postcode.
Go to postcode.royalmail.com if the recipient is not listed elsewhere. This will take you to the Royal Mail's postcode search form.
Fill out the form. The main form asks for a building number, name, street and town. If you need to search by a flat number, click on "Detailed Search."
Click on "Find Postcode." Your postcode results will be shown on the following page.
Refine your search with any additional information you might have if the page contains too many postcode options.