If you wish to communicate with the credit bureaus through mail them these are the postal addresses. Listed are also their websites.
Equifax P.O. Box 740 4256 Atlanta, GA 30374 Website: www.Equifax.com
Experian P.O. Box 2002 Allen, Texas 75013 Website: www.Experian.com
TransUnion P.O. Box 390 Springfield, PA 19064 Website: www.TransUnion.com
It is much simpler and faster to communicate with credit bureaus online. However, certain kinds of procedures may require communicating over the postal mail. Many people would prefer to send letters, requests and disputes through post, specially if you are sending copies of documents as well. Not everyone likes to scan everything, convert it to size and then email it.
Usually, all communication is sent through registered post. However, there are 2 school of thoughts to say whether you should or not request a ‘receiving receipt’ as well. Return receipt provides the proof that your letter or dispute has been received. However, I have also read that credit bureaus simply ignore and do not accept letters sent with return receipt requested. This practice is in no way an ethical one, but that does not mean that they do not do it.