What is a letter subject line?

A letter subject line is an optional line near the top of a formal letter that states the main subject of the letter.

In the US, the subject line typically appears after the date but before the salutation, with a line of blank space before and after it.

Subject lines often start with “Subject:” (e.g., “Subject: Plumbing Awards 2025”) or “RE:” for “regarding” (e.g., “RE: Your table at the Plumbing Awards 2025”).

QuillBot’s free AI Humanizer can help you to improve AI-generated letter content.

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Who can write a letter of recommendation?: Who can write a letter of recommendation depends on the application type.

To be able to write a strong letter, the recommender needs to know the applicant well so they can speak from firsthand experience.

College applicants, for instance, typically ask one or two of the following trusted figures to write a letter of recommendation for them:

A high school teacher

A high school counselor

An employer

A leader of an extracurricular activity

QuillBot’s free Paraphraser can help you draft a polished, effective email to ask someone to write a letter of recommendation for you.
What is the difference between a letter of reference and a letter of recommendation?: The terms letter of reference and letter of recommendation are often used interchangeably.

In the U.S., however, a “letter of recommendation” typically refers to a letter written for a specific application (e.g., to college or graduate school) that is tailored to the opportunity in question. A “letter of reference,” on the other hand, usually refers to a general endorsement (e.g., written by a person’s employer when they leave a job) that can be used for multiple future applications.
How should you ask for a letter of recommendation from an employer?: When asking for a letter of recommendation from an employer, offer to make the process as easy as possible for them by:

Giving them suggestions for statements they could include in the body of the letter (e.g., sentences with specific examples of projects, achievements etc. that your potential recommender has witnessed firsthand)

Providing them with all the background information they need (e.g., details of the job you’re applying for and the requirements of the job)

Ask for a strong letter of recommendation to signal that they should decline if they can only write you a generic or weak letter.You can use a tool like QuillBot’s free Paraphraser to help you write compelling descriptions of your strengths, qualifications, and achievements.
What is a good resignation subject line?: If you are writing a resignation letter and want to attach it to an email, possible subject lines include:

Notice of Resignation

Resignation Notification

Letter of Resignation

Try QuillBot’s Paraphraser tool in Formal mode to help you write your letter of resignation.
What should I include in a short resignation letter?: A short resignation letter in the US includes the following essential elements.

Your mailing address and other contact details

The date you are submitting the letter of resignation

A salutation (e.g., “Dear Jane:”)

A resignation statement specifying your last day (e.g., “Please accept this letter as formal notice of my resignation as [Your job title] at [Name of organization]. My last day of work will be [Date].”)

Your name and signature

To create a more professional impression, also include a reason for leaving, some words of gratitude, and an offer to assist with the transition of your duties.

Use QuillBot’s free Grammar Checker to help you proofread your letter of resignation.
What is a good resignation letter format?: A resignation letter is a formal letter that should be written in an appropriate format, such as the block letter format.

This format uses a standard font such as Times New Roman or Arial, with a font size of 10–12 points and single line spacing. The text is aligned to the left margin, including the start of paragraphs, and you leave an empty line between each element of the letter.

The essential elements of a letter of resignation in the US are:

Your contact details

The date

A salutation (e.g., “Dear X:”)

A statement of resignation specifying your last day (e.g., “I am writing to inform you that I am resigning from my position as [Job title] at [Name of company/organization] effective from [Date], which will be my final day.”)

Your name and signature

You will create a better impression if you also include a reason for your departure, an expression of thanks, and an offer to help with the transition of your responsibilities.

Why not use QuillBot’s Paraphraser tool in Formal mode to help you craft an effective letter of resignation?
What are some funny farewell messages for work colleagues?: Funny farewell messages for work colleagues include:

Have fun storming the castle!

I’ll think of you every time I’m not on a Zoom call.

See you when you come back to work for us next year!

Who’s going to do all my work for me now?

See ya’ later, Alligator!

Take me with you!

Even when you’re being funny, typos are no joke, so why not run your messages through QuillBot’s free Grammar Checker? It will fix errors in any farewell messages for coworkers.
What are some things to write in a coworker’s farewell card?: Some things to write in a coworker’s farewell card include:

You’re going to do great things!

Thanks for all of your support and mentorship.

You’re amazing at what you do.

I learned so much from you.

It won’t be the same here without you.

Congratulations on your new job!

It was an honor to collaborate with you.

You only get one chance to sign a farewell card, though, so why not type your message first and run it through the QuillBot Grammar Checker? It will instantly spot errors in any type of farewell message to a coworker.

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What is a letter subject line?

Professional writing: Other interesting questions