• Remove mail from mailbox as soon as possible after delivery
• Never leave mail in mailbox overnight. (The Postal Service will hold mail for you at no charge by submitting a hold order either at your local post office or via the USPS website) 
• If you travel frequently, consider the security of renting a post office box
• Deposit outgoing mail only in blue Postal Service collection boxes or at your local post office. Do not place outgoing mail in your personal mailbox or in your apartment complex outgoing mail slot
• Keep track of monthly financial statements
• Promptly contact the senders if you do not receive credit cards, checks, or other valuable mail
• Purchase a paper shredder or otherwise destroy any unwanted mail that contains financial or personal identifier information
• Use a gel-type ink to write checks: it is much more difficult to chemically remove
• If you see suspicious persons or activity, call 911 while the suspects are still present
• To "opt out" of receiving pre-approved credit and insurance offers from the credit bureau mailing lists call: 1-888-5-OPTOUT (1-888-567-8688) or visit OptOutPrescreen 
• If your mail is stolen, report it immediately to the U.S. Postal Inspection Service or call 877-876-2455 to file a mail theft complaint via telephone
• Do not use the red flag on your mailbox, it flags thieves, too 

 Special thanks to the United States Postal Inspection Service's for providing these tips.