Endorsing a check properly is an essential aspect of banking. Endorsing a check incorrectly may cause the check to be returned.

[edit] Steps

Personal Checks

An endorsed check.

Write "For Deposit Only" on the left of the back side if you're depositing the check.
Sign your name on the next line, writing your name as it is made out on the front.
Write your account number below that.
Write only at the top of check. Many checks will say "do not write, stamp or sign below this line" to help you comply with this policy.

Business Checks

Endorse the check on the reverse with the following: Business Name, Your Name, and position in the company. Example:

    Jim's Hardware Store
    James Smith
    Owner

Write "For Deposit Only" below the endorsement.
Write your account number below that.

Insurance Checks

This is for checks made payable to an individual, a party, or another financial institution. For example, "Pay to: John Doe, Jane Doe & Wells Fargo Mortgage"

Have each party sign the check.
Request that an agent from the financial institution endorse the check. They will most likely write additional information or stamp the check below their signature.

[edit] Tips

To sign over a personal check, write "pay to the order of John Doe" at the top, and replace "John Doe" with your recipient. Then sign your name below that. John Doe will need to sign below your name.
For multi-party checks, addressed to two or more people with the word(s) "OR", either part may endorse the check.
For multi-party checks, addressed to two or more people with the word(s) "AND", all parties must endorse the check.
For checks written to a minor, the minor cannot endorse the check. A parent or guardian will need to endorse the check. Write: "Parent/Guardian of [Child's Name], Minor" below the endorsement.
To save a lot of time and hassle one option is to get a stamp like this:
- You won't have to remember your account number and it spells out your instruction for you so that you don't have to sign the check.
- With this stamp your check cannot be cashed by anybody except you; nor can it be deposited to any account except yours.
A cheaper way to accomplish the same thing is to set up a word document for check endorsing. Type the words: "For Deposit Only to the account of (your name)" and put your account number on the next line. Set up your document so that it will print on a check sized piece of paper and put the icon on your desktop for easy access.
If your name is misspelled on a check (i.e. Sara Jones, if your real name is Sarah Jones), endorse the check as it is written on the front of the check, then sign the correct spelling below it.
Some financial institutions do not require checks to be endorsed before cashing or depositing it. Check with your bank to see if they require this process.

[edit] Warnings

Never sign your signature without the words "for deposit only" on the back of a check unless you are physically at the bank. These words prevent someone from endorsing their name below yours in order to be able to wrongfully gain control of your check and the money it represents.
Insurance Checks are frequently returned for improper endorsement. Endorse it EXACTLY as name(s) are written on the front of the check
Note that it is not required to write the account number on the back of a check that you are depositing. It is sufficient to write "For Deposit Only." Some security experts advise that writing your bank account number on the back of a check is a security risk in that it exposes your account number to third parties who may handle the check.