The short answer is yes. You should definitely send a well crafted and custom cover letter when applying to employer or recruiter job openings. If it is prepared correctly it will seal the deal for an interview. Unfortunately, most job seekers do not write and structure it the right way to actually help their cause. Recruiters, hiring managers, staffing professionals, and basically everyone else involved in the hiring process finds them useful and helpful most of the time. At the very least, they let the person know this person who just sent me their resume is sincerely interested in the position being offered and isn't wasting my time.
You may not know but people blast off resumes without even reading the job description or researching the company? A cover letter lets me know I am ot about to burn some time with this person. Basically, there is zero downside in sending a tailored cover letter and only an upside. If you do decide to send one, which you should, prepare it correctly. Like the endless resumes I review day after day, most cover letters are not good, and should not even be sent. The goal is to impress employers, not make them question you.
The tone and content of the letter should be consistent with the kind of position for which you are applying. A junior level opportunity will permit much more latitude than a more senior executive. Do not come across as overly desperate or aggressive in your writing. Be straightforward, succinct, and positive. Do not write it like you are sitting down to write your biography. Most people do not read biographies of famous people, so they surely will not be interested in your life story, no offense. The wrong information in a cover letter will certainly hurt your chances for an interview, as much as not sending one at all. Like the resumes I see, your prespective is not going to be the same as someone doing the hiring.
Hiring managers are busy and will not wade through fluff and nonsense. Your opening paragraph should clearly state some key items to get them involved and want to look further. The body of your letter should contain the sales pitch. Remember, you are selling a service to employers in exchange for money. This is your chance to outline the top reasons why you are worthy of an interview. Demonstrate how your credentials, motivation, and track record would benefit their operation. Many people spend too much time on this part of the cover letter citing irrelevant details from their work experience.
Keep your letter positive and upbeat. This is not the place to write a sob story about your employment situation. Put yourself in the hiring manager's shoes. Would you call yourself in for an interview? Never mind, don't answer that. Keep the length of your cover letter reasonable. Recruiters and hiring managers often receive hundreds of resumes for many positions. Your final paragraph should generate a call for action, so express your strong interest in an interview and state that you will follow up soon to confirm your resume was received and discuss the possibility of meeting face-to-face.
Reprinted by Permission: Professional Recruiter Org