The cover letter is your chance to show your communication skills, since your resume should be concise and does not say much about your writing ability. So, I do not believe there is a set rule for cover length... it all depends on the job. If you use a formal letter heading at the top (your address, their address, a salutation), and a Sincerely section at the bottom, that takes up about 1/4 of a
. page already. The other 3/4 should be used wisely. From my experience, and speaking with HR professionals, length is not as important as how easy it is to read. Make sure there is a good amount of white space! Don't squeeze everything into huge paragraphs with a 10 pt font. Sometimes it takes less time to read a longer cover letter that flows nicely and has a good balance of white space than a shorter cover that does not flow nicely.
