Cracking the Code: 25 Must-Know Acronyms for Business Emails

Have you ever opened a business email and wondered what acronyms like OOO, EOD, or KPI mean? You’re not alone!

In the fast-paced world of professional communication, using acronyms instead of full words can save time. But if you’re an English language learner—or a native speaker who isn’t familiar with business jargon—you might start scratching your head when you see all those letters.

Don’t worry! This guide will decode 25 acronyms that are commonly used in business emails and unlock the meanings behind all that “alphabet soup”. You’ll be able to understand acronyms—and use them yourself—in no time.

Here they are…25 business acronyms to watch out for

Below you will find a list of common acronyms, what they stand for, and an example sentence to show you how each one is used. The acronyms are in alphabetical order, so whether you’re looking for the meaning of ASAP or YTD or something in between, you can easily find what you need.

1. ASAP – As Soon As Possible

• I need those year-end reports ASAP.

2. B2B – Business-to-Business

• Our company provides B2B software that will improve efficiency and streamline your operations.

3. B2C – Business-to-Consumer

• The B2C market exploded at the end of the 20th century with platforms such as Amazon and eBay.

4. CEO – Chief Executive Officer

• Mary Barra is the CEO of General Motors.

5. CFO – Chief Financial Officer

• I met with the CFO and he said the company doesn’t have the funds for a project of this magnitude.

6. COB – Close Of Business

• Please contact Oleg and go over the numbers with him by COB today.

7. CRM – Customer Relationship Management

• This new CRM system will help us track our customers’ data more efficiently.

8. CSR – Corporate Social Responsibility

• Our company has recently launched a CSR campaign to promote health and wellness in the underserved communities near our headquarters.

9. EOD – End of Day

• I need everyone to turn in their health insurance forms by EOD on Thursday.

10. ETA – Expected Time of Arrival or Estimated Time of Arrival

• What is the ETA for the Japanese delegation?

11. FYE – Fiscal Year End/Fiscal Year Ending

• Our FYE is June 30, so please plan accordingly.

12. FYI – For Your Information

• FYI, our order from the supplier has been delayed until the end of the month.

13. HR – Human Resources

• Have you notified HR about our need for an improved onboarding process?

14. KPI – Key Performance Indicator (This acronym is often pluralized as KPIs)

• Chris will be going over several KPIs, including website traffic, customer retention rates, and in-store purchases.

15. IMO – In My Opinion

• IMO, an advertising campaign on TikTok will reach our target audience more effectively than a campaign on Facebook.

16. N/A – Not Applicable

• These sales figures from 2019 are N/A to our current situation.

17. NDA – Non-Disclosure Agreement

• Before you start your position at this company, you must sign an NDA.

18. NRN – No Reply Necessary

• Here is the draft version of the article—NRN unless you find typos or mistakes.

19. OOO – Out of Office

• Both Hana and Larry will be OOO on Monday, so contact me if you run into any issues.

20. OTOH – On The Other Hand

• Barbara said we could move forward with the new software installation, but OTOH, it might be better to wait until after the holidays.

21. PTO – Paid Time Off

• I am taking PTO from December 20 through January 5.

22. ROI – Return On Investment

• This marketing campaign has given us a solid ROI.

23. TBD – To Be Determined or To Be Decided

• The host city for the conference is TBD.

24. TL;DR – Too Long; Didn’t Read

• The report that Brian sent was TL;DR.

25. YTD – Year To Date

• Their YTD sales have exceeded all expectations, so I think this is a good company for us to partner with.

Some common questions about using acronyms in business emails

Question #1: Do you have to put a period between each letter in an acronym?

Answer: You may have once had an English teacher who told you to always put a period after each letter in an acronym (e.g., I.M.O. instead of IMO). However, in most modern writing—especially business, tech, and online communications— we don’t put periods between the letters in common acronyms and initialisms. This no-periods approach improves readability and efficiency.

However, if you are doing some type of formal writing where you must adhere to a style manual that requires a period after each letter in an acronym, then you should include them. But in most business contexts, this isn’t necessary.

Question #2: Should the letters in an acronym be capitalized?

Answer: Yes, all of the letters in an acronym should be capitalized. At TextRanch, we often see “asap” instead of “ASAP” and “fyi” instead of “FYI”. If you are using these acronyms in a very casual/informal context, such as a text message to a friend, then it’s okay if they aren’t capitalized. But in professional contexts, you should use all capital letters when writing acronyms.

Question #3: Are there contexts where we should write out the actual words instead of using acronyms?

Answer: Yes. Please see the next section of this article!

When to avoid acronyms

As stated earlier, acronyms can save time and speed up your business communications. But they can also be confusing—hence, the reason for this article.

If you find yourself in one of the situations described later in this section, you can still use acronyms. You just need to introduce the actual words first, followed by the acronym in parentheses. Then you can go ahead and use the acronym in subsequent sentences.

Here’s an example:

• The company’s Key Performance Indicators (KPIs) show steady growth through the first quarter of 2024. You may view these KPIs in more detail in the attached file.

This example sentence provides the readers with the actual words as well as the corresponding acronym. It’s also written in plain English, making it easy to understand.

You should use this format, or something similar, when:

1. Your audience isn’t familiar with the acronyms you are using.

Are you communicating with external stakeholders, new employees, English language learners, professionals in other fields, or the general public? Don’t bombard them with a lot of “alphabet soup”. It will be much easier for them to follow along if you define acronyms upon first use.

2. An acronym you want to use has multiple meanings.

In the business world, PTO is a common term that refers to paid time off. But in an educational setting, those letters can stand for Parent-Teacher Organization. So if you’re in a setting that includes professionals from different fields, it’s important to be clear about the acronyms you are using.

3. You are writing a legal document or academic paper.

In legal or academic writing, it is standard to write out the actual words with the acronym in parentheses the way we did with the KPIs example at the beginning of this section. However, it’s a good idea to consult an appropriate style manual to make sure you are formatting everything properly.

4. The acronym disrupts readability.

Too many acronyms within a short text can make the writing difficult to understand. Limit their use to avoid overwhelming your readers.

Are you still struggling with acronyms? Click the blue button below. One of our TextRanch editors will look at your writing and provide you with corrections and feedback.

To avoid the dreaded TL;DR, we are done for now!