Generic cover letters get ignored. Fully custom ones take an hour you do not have when you are applying to ten roles a week. The fix is not picking one extreme. It is a short list of high-impact personalization moves that take five minutes and make a base letter read like it was written for this specific job.
Name the company in the first line
The fastest signal that a letter is not a mass mailing: the company name in the opening sentence, used naturally. Not "I am writing to apply for the position" but "I have followed how [Company] approaches [specific thing] for a while."
This one change costs you ten seconds and removes the strongest tell of a template. Do it every time.
Mirror the job title and two keywords
Use the exact job title from the posting, not your own paraphrase. If they say Product Marketing Manager, do not write marketing manager. Then pull two or three concrete phrases from the requirements, the ones that read like real priorities, and weave them into a sentence about your experience.
This does two jobs at once. It reads as personalized to a human, and it matches the keywords an ATS scans for. You are not stuffing keywords, you are reflecting their language back.
Add one specific reason for this company
Pick one true, specific thing about the company and say why it matters to you. A recent product launch, a value they state and actually live, a market they are moving into. One sentence.
Specific beats flattering. "I admire your commitment to excellence" is filler. "Your move into the SMB segment is the kind of problem I want to work on" is personalization. The second one could not be copied into another application.
Match one achievement to their top need
Read the posting for the single most important thing they want, usually in the first two bullets. Then lead your evidence with the achievement that maps to it. You are not writing new content, you are reordering what you already have so the most relevant proof comes first.
A reader spends seconds deciding whether to keep going. Put the most relevant achievement where they will see it, not buried in paragraph three.
Build a reusable base so this is fast
The five-minute version only works if you have a strong base letter to personalize. Write one solid version, then keep the openings and the company-reason line as the parts you swap each time. Everything else stays.
If you are sending out a CV alongside the letter, keep them consistent. A tool like Postulit can build your CV from your LinkedIn profile, which gives you a clean source of achievements to pull from when you tailor each letter.
The takeaway
Do not choose between generic and exhausting. Name the company up front, mirror their job title and keywords, add one specific reason, and lead with the achievement that matches their top need. Five minutes per application, and the letter stops looking like a template.