Knowing which letter to send can be just as important as knowing how to write one.
This guide covers the key differences between a letter of interest and a cover letter so you can choose the right approach and give your application its best chance.
Is a letter of interest the same as a cover letter?
No. A letter of interest and a cover letter serve different purposes and are used at different points in a job search.
A cover letter accompanies a resume in response to an advertised role, while a letter of interest reaches out to a company before any vacancy has been posted.
One is reactive, the other is proactive.
What are the main differences between a letter of interest and a cover letter?
The simplest way to decide: is there a job posting?
If yes, write a cover letter.
If no, write a letter of interest.
Beyond that, the two documents differ in purpose, tone, timing, and what they need to achieve.
| Cover letter | Letter of interest | |
|---|---|---|
| Trigger | A specific advertised job opening | No open role; proactive outreach |
| Purpose | Demonstrate fit for a defined position | Open a conversation and get on the employer's radar |
| Tone | Targeted and role-focused | Broader, company-focused, exploratory |
| Resume attached? | Yes, always | Usually, but not required |
| References | Job title, requirements, role responsibilities | Company mission, culture, your transferable value |
| Expected outcome | An interview for the advertised role | Consideration for future or unadvertised positions |
| When to send | During an active application process | Any time, regardless of hiring cycle |
| Who reads it | Hiring manager for that role | Often a recruiter or HR contact |
A useful way to remember the distinction: a cover letter is transactional and a letter of interest is relational.
One closes a gap between your experience and an open role.
The other builds a connection with a company you want to be part of, before the gap even exists.
How do the formats of a letter of interest and a cover letter differ?
Both letters share the same three-part structure: an opening, a body, and a close.
What goes into each part is where they diverge, because the reader's expectations are not the same.
| Section | Cover letter | Letter of interest |
|---|---|---|
| Opening | Name the role and lead with your strongest relevant qualification | Name the company and explain specifically why you are reaching out |
| Body | Match your experience to the job description and requirements | Highlight your skills, key achievements, and the value you could bring |
| Close | Request an interview and state your availability | Invite a conversation and ask to be considered for future roles |
| Length | Half a page to one full page; no more than 400 words | Similar length; concise enough to respect the reader's time |
| Research needed | Job description and company background | Deeper company research: mission, values, recent news |
The most meaningful format difference is in how much company research each letter demands.
A cover letter requires you to understand the role.
A letter of interest requires you to understand the company.
The more you demonstrate genuine knowledge of their work and direction, the more your outreach will stand out from a generic enquiry.
How do I decide whether to write a letter of interest or a cover letter for my application?
Start with one question: is there a job posting?
That answer determines which letter you need.
According to Resume.io research, 88% of hiring managers engage with unsolicited applications and 40% say clear alignment with the company's needs is what makes one stand out.
Candidates who consistently submitted cover letters with applications received job offers at a rate of 35.8%, compared to 21.2% among those who never submitted one.
Use a cover letter when:
- You are responding to a role advertised on a job board, company website, or through a recruiter.
- The application process includes a closing date, an application portal, or a named hiring manager.
- You have been referred to a role and are submitting a formal application.
Use a letter of interest when:
- You want to work at a company but cannot find an open role that matches your background.
- A contact has told you the company may be hiring soon, but nothing has been posted publicly.
- You have seen news about a company expanding, entering your sector, or launching a new division.
- You want to get on a recruiter's radar ahead of future hiring cycles.
Browse our cover letter examples or templates if you are ready to start writing.
When might a letter of interest work against you?
A letter of interest can create the wrong impression if it is not handled carefully.
Knowing when not to send one is just as useful as knowing when to.
Avoid sending a letter of interest when:
- It is not personalized to the company. Hiring managers can identify a generic letter immediately, and most will not respond to one.
- The company is in a hiring freeze, has recently announced layoffs, or has stated it is not accepting unsolicited contact.
- An open role already exists that matches your background. A cover letter tied directly to that position is always the stronger choice.
- You have not done enough research to speak to the company's work, values, or direction.
A vague enquiry tends to be filed rather than acted on.
The effort you put into understanding a company before you write is what separates a letter that gets a response from one that does not.
What do hiring managers actually think when they receive each letter?
The two documents land in completely different contexts, and hiring managers approach them accordingly.
A cover letter is read as part of a formal application.
The question being asked is simple: does this person fit what we need right now?
If that answer is not clear within the first few lines, the letter may not get further consideration.
Strong cover letters are precise, role-focused, and make the connection between experience and requirements easy to see.
A letter of interest is read with more curiosity than evaluation.
Most do get attention, which is why the research effort is worth making before you send one.
What separates a memorable letter of interest from a forgettable one:
| What works | What does not |
|---|---|
| Referencing a recent company initiative or news | Generic praise ("innovative," "industry-leading") |
| Naming a challenge in their sector you can help with | Vague statements about wanting to contribute |
| Demonstrating knowledge of their culture or values | Copying the same letter to multiple companies |
| Showing what you offer, not just what you want | Focusing on your career goals rather than their needs |
The practical difference: a cover letter rewards precision.
A letter of interest rewards genuine curiosity and research.
Key takeaways
- A cover letter responds to an advertised job opening; a letter of interest reaches out to a company before any role has been posted.
- The decision comes down to one question: is there a job posting? If yes, write a cover letter. If no, write a letter of interest.
- Both letters share the same basic structure, but a cover letter focuses on the role while a letter of interest focuses on the company.
- Letters of interest are worth sending: Resume.io research found a majority of hiring managers engage with unsolicited applications, but only when they demonstrate genuine knowledge of the company.
- If an employer labels something a "letter of interest" within a job posting, treat it as a cover letter and tailor it directly to the role.
Frequently asked questions
Understanding these two documents puts you in a stronger position at every stage of your job search, whether you are responding to an opening or creating an opportunity that does not yet exist.
Can I send a letter of interest even if a company is not hiring?
Yes, and it is exactly what a letter of interest is designed for.
Most hiring managers do engage with unsolicited applications, so the effort is rarely wasted.
Make yours count by demonstrating real knowledge of the company and explaining clearly the value you could bring.
Do I need to attach a resume to a letter of interest?
In most cases, yes. Including your resume gives the hiring manager something concrete to act on if your letter sparks interest.
Without it, they would need to follow up before they can consider you, which is a step most will not take.
What if an employer calls something a "letter of interest" but it is for an advertised role?
Treat it as a cover letter. If there is a job description and an application process, write directly to the requirements of that role regardless of what the employer has called the document.
You can also explore a letter of introduction or a short cover letter if the role calls for a lighter-touch approach.
Follow the instructions in the posting and tailor your letter accordingly.
