For printed cover letters or those sent as attachments
Will contain your contact details, the recipients name and address, the title of the position, the date and location where you saw the advertisement, and the opening salutation.
Sometimes the advertisement will not tell you who the recipient is, in these cases avoid using “to whom it may concern”, “Dear Sir”, “Dear Madam”, use “Human Resource Professional”, “Human Resource Manager” instead, you may even use the company name in the salutation.
For cover letters sent as the body of an email.
In these cases there is no need to add the postal address, though you will need to include the date and where you saw the advertisement and address the recipient by name if known. When replying to posted advertisements, read their instructions on how to apply, as they may require that you list a specific job code or use a certain phrase in the subject line.