If it’s to an individual, include both their first and last names. If they are a ‘Jr. ’ or a ‘Sr. ’ you should include this as well. If the check is going to an organization, write out its full name. Do not use acronyms unless explicitly given permission. A check is a legal document because it is signed and dated, and the recipient needs to sign it also. The bank is a legal institution that can deny the check being cashed/deposited with missing information.