Cover letters can be one of the most challenging parts of applying to a job. They're more like writing an essay than a concise list of bullets outlining your achievements, as in your resume.

Still, 89% of recruiters expect job candidates to submit them, according to Zety's 2025 Future of Work Report, which surveyed 753 recruiters or HR professionals involved in hiring.

HR consultant Stefanie Fackrell, who's worked as a recruiter at companies like Nvidia and Google, is "doubtful" it's really that many. Still, she says, you should "have a well written, compelling cover letter on hand at all times."

That's because especially in this highly competitive job market, "if someone is submitting a cover letter, if it's optional, that can help somebody stand out from the crowd," she says. Here's when it might be OK to skip one, and how to go about writing one when you do need it.

You could skip it 'if you're a technical professional'

There are a few instances in which you might be able to avoid writing and submitting a cover letter. "If you're a technical professional" like an engineer, says Fackrell, "you're probably not going to have to submit a cover letter."

Career coach Phoebe Gavin outlines a few other instances in which you might be able to forgo one: "If a recruiter reaches out to you directly, asking only for your resume. If the application platform or system explicitly states not to include one. If the application includes specific questions that replace the purpose of a cover letter."  

Still, says Gavin, "submitting a cover letter (unless explicitly instructed otherwise) will rarely, if ever, hurt your chances."

'Avoid rehashing your resume'

The benefit of submitting one, whether your prospective employer asks for it or not, is that "the cover letter is an opportunity to shape the narrative of your candidacy and ensure the hiring manager understands how your experiences align with their needs," says Gavin.

She and Fackrell list a couple of tips for writing one:

• "Avoid rehashing your resume," says Gavin. "Instead, explain how your approach to work and unique skills align with the job's needs."
• "If you have big recent gaps in your employment, are making a career switch, or might be perceived as overqualified," says Gavin, "briefly explain these points in a way that reinforces your candidacy. For example, if you're transitioning to a new field, clarify your enthusiasm for this direction and highlight transferable skills."  
• Remember to add a bit of personality to your cover letter to give them a sense of who you are and help you stand out. "If you're going for a travel industry role," says Fackrell as an example, "maybe you could say, 'I've traveled to 100 countries.'"

In terms of length, keep it short.

Have an opening paragraph that talks about why you applied, a second paragraph that dives into details about your history, "and then a quick closing just expressing your enthusiasm for the position," says Jasmine Escalera, career expert at Zety.

Keep it "maximum one page," she says.

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