COB vs. EOD: Understand Meaning, Key Difference, And Use

Most professionals use business acronyms in their emails. Some acronyms have similar meanings, and it becomes harder to understand how to use those business acronyms effectively.

COB, EOD, COP, EOP, and EOD are among those acronyms usually used for the same purpose will little differences.

We have explained these business acronyms with examples to bring more clarity so you can use them effectively in your emails.

What does COB mean in business?

COB stands for the close of the business day.

It also represents the close of the financial markets in New York City. But when you use COB in your business emails, it depends on your local time zone and working hours.

Here is what COB means in your business emails.

If your boss, manager, or co-worker has used the term COB in the email, they want you to take action before the end of the mentioned business day. If they haven’t mentioned any day with COB, it means it’s today.

But usually, professionals mention a day after the term COB. It usually looks like the COB date or day.

For instance, you might have received an email to take some action COB today, tomorrow, or COB 15th of the current month.

It means you should complete the tasks before that business day ends. If it’s COB today, it means you should meet the tasks before the close of business today. If it’s COB tomorrow, it means the close of business tomorrow. If it’s a specific today like Monday, Wednesday, or Friday, it means the close of the business on that particular day.

But here comes the problem. A business day can close in different time zones. If you are from Sydney and received an email from your company’s headquarters in New York, the close of the day will be different for both regions.

In that case, the sender must mention their time zone. For instance, your boss’s COB today will be 5:00 PM EST (eastern standard time).

Let’s understand a business day and how it can help us better understand acronyms like COB, EOD, COP, etc.

What is a business day?

A business day is any working day, Monday to Friday, usually from 9:00 AM to 5:00 PM.

In some countries, the business day starts at 8:00 AM and closes at 4:00 PM. In such countries, the deadlines will depend on their working hours.

Now, as you know, a business day totally depends on the working hours of a specific region, so using the COB for emails within the office or local area won’t cause any confusion. Locally, COB has the exact closing time for all employees.

As all the employees have the same working hours, the COB will refer to the close of the mentioned business day.

For instance, COB today in the UK will refer to the close of the business day today (typically at 5:00 PM).

Remember that Saturday, Sunday, Christmas day, or other approved holidays are not business days.

What EOD stands for?

EOD stands for the end of the day. It refers to the calendar day you are working in.

Professionals also use EOD as an alternative to COB today. But the key difference is the ending time of both. EOD (if not mentioned in the email) will be at midnight.

COB vs. EOD: What’s the key difference?

COB and EOD are synonymous with each other. You can interchangeably use both for each other. But the key difference between COB and EOD is that COB means the deadline is 5:00 PM, and for EOD, it’s 11:59 PM.

However, you can mention the time with EOD in your emails to specify the time. For instance, you can say EOD Friday (5:00 PM).

Does EOD go before or after the date?

EOD means the end of the day, and the EOD date represents the end of that mentioned day. So it goes neither before nor after the date but before the closing date.

EOD may also represent a non-business day. And it ends at midnight.

Can COB mean midnight?

COB (close of the business day) doesn’t mean midnight. Although, EOD (without time mentioned) means midnight.

However, EOD (5:00 PM) will represent a business day.

How do you write COB in an email?

Here is an example of using COB in an email.

For instance, if you want your employees to complete the task by tomorrow, here is how you can appropriately use the acronym COB in your email.

Hi Kim,

I have attached all the details of the work. We have to provide the report to the client by COB tomorrow.

Thank you,


Here is something important to understand.

If you are communicating with someone from any other region, the best is to mention the time zone. And if it’s a sensitive email, it’s better to avoid acronyms for clarity. The more specific you become, the more influential the email will be.

Should I use COB or EOD?

There is nothing wrong with using acronyms. COB and EOD are synonymous with one another.

The key difference between COB and EOD is that EOD may represent a non-business day. EOD may also end at midnight.

So it’s up to you what time frame you have in your mind. If you want something before the working hour’s end, the best is to use COB.

COB synonyms

As we have discussed earlier, COB stands for the close of the business day. It also represents the close of the financial markets in New York City.

Some other acronyms are synonymous with COB and are used in business emails.

If you are looking for the best alternatives to COB to use in your emails. Here are the most appropriate words with the same meaning for professional emails: End of business (EOB), end of the day (EOD), end of the play (EOP), close of the play (COP), and close of business (COB).

COP (end of the play) also represents the close of the financial markets in New York City. So COP (close of the play) and EOP (end of the play) are the best alternatives to COB (close fo the business).