EDATE and EOMONTH in Excel - Step-by-Step Guide

Introduction

EDATE and EOMONTH are Excel functions that help you work with dates easily. They let you find a date a certain number of months before or after a given date, or find the last day of a month. This is useful when you want to calculate due dates, expiration dates, or monthly reports.

When you want to find a date exactly 3 months after a project start date to set a deadline.

When you need to calculate a credit card expiration date 12 months from the issue date.

When preparing monthly sales reports and you want to find the last day of each month automatically.

When calculating employee contract end dates based on a start date plus a number of months.

When setting reminders for subscription renewals that happen every few months.

Steps

Step 1: Click

- a blank cell where you want the result

The cell is selected and ready for input

Step 2: Type

- the formula bar

The formula is entered in the cell

💡 Start with =EDATE or =EOMONTH to use these functions

Step 3: Enter

- the EDATE formula as =EDATE(start_date, months)

The cell shows the date that is the given number of months before or after the start_date

💡 Use a positive number for months to go forward, negative to go backward

Step 4: Enter

- the EOMONTH formula as =EOMONTH(start_date, months)

The cell shows the last day of the month that is the given number of months before or after the start_date

💡 This is useful to find month-end dates for reports or billing

Step 5: Press

- Enter key

The formula calculates and displays the date result in the cell

Before vs After

Before

Cell A1 contains 01/01/2024, and cell B1 is empty

After

Cell B1 contains 04/01/2024 after entering =EDATE(A1, 3), showing the date 3 months after Jan 1, 2024

Settings Reference

start_date

📍 Formula argument

The date from which to calculate the new date

Default: No default, must be provided

months

📍 Formula argument

Number of months to add (positive) or subtract (negative) from start_date

Default: No default, must be provided

Common Mistakes

Entering months as text with quotes like "3"

Excel treats text differently and the formula may return an error or wrong result

Enter months as a number without quotes, like 3 or -3

Using EDATE when you want the last day of the month

EDATE returns the same day of the month, not the month-end date

Use EOMONTH to get the last day of the month

Summary

EDATE calculates a date a set number of months before or after a start date.

EOMONTH finds the last day of the month a set number of months before or after a start date.

Always enter months as numbers without quotes and provide a valid start date.

Practice

1. What does the EDATE function do in Excel?

easy

A. Returns the last day of the current month.

B. Returns a date that is a specified number of months before or after a given date.

C. Calculates the number of days between two dates.

D. Returns the first day of the month for a given date.

Solution

1. Step 1: Understand the purpose of EDATE

   The EDATE function is designed to add or subtract whole months from a given date.

2. Step 2: Compare with other date functions

   Unlike functions that return the first or last day of a month, EDATE returns the same day number in the new month or the last day if that day doesn't exist.

3. Final Answer:

   Returns a date that is a specified number of months before or after a given date. -> Option B

4. Quick Check:

   EDATE adds/subtracts months = A [OK]

Hint: EDATE shifts months keeping the day number [OK]

Common Mistakes:

• Confusing EDATE with EOMONTH
• Thinking it returns the last day of the month
• Assuming it calculates days difference

2. Which of the following is the correct syntax for the EOMONTH function?

easy

A. EOMONTH(start_date, months)

B. EOMONTH(months, start_date)

C. EOMONTH(date)

D. EOMONTH(start_date)

Solution

1. Step 1: Recall EOMONTH syntax

   EOMONTH requires two arguments: the start date and the number of months to add or subtract.

2. Step 2: Validate argument order

   The first argument must be the start date, followed by the months offset.

3. Final Answer:

   EOMONTH(start_date, months) -> Option A

4. Quick Check:

   Correct syntax = D [OK]

Hint: Start date first, months second in EOMONTH [OK]

Common Mistakes:

• Swapping the order of arguments
• Providing only one argument
• Using invalid argument types

3. If cell A1 contains the date 2023-01-31, what will =EDATE(A1, 1) return?

medium

A. 2023-02-28

B. 2023-02-31

C. 2023-03-02

D. 2023-01-31

Solution

1. Step 1: Understand EDATE behavior with end-of-month dates

   EDATE tries to keep the same day number. Since February 2023 has only 28 days, and 31 doesn't exist, it returns the last day of February, 2023-02-28.

2. Step 2: Confirm the calculation

   One month after January 31, 2023, adjusted to last valid day in February.

3. Final Answer:

   2023-02-28 -> Option A

4. Quick Check:

   EDATE adjusts to last valid day = 2023-02-28 [OK]

Hint: EDATE returns last valid day if day number missing [OK]

Common Mistakes:

• Expecting day 31 in February
• Confusing EDATE with EOMONTH
• Ignoring fewer days in February

4. You wrote =EOMONTH(A1) to get the last day of the month for the date in A1, but it shows an error. What is the problem?

medium

A. EOMONTH cannot be used with cell references.

B. A1 does not contain a valid date.

C. EOMONTH requires two arguments; months argument is missing.

D. The formula should be written as =EOMONTH(A1, 0) to get the current month's end.

Solution

1. Step 1: Check EOMONTH function requirements

   EOMONTH needs two arguments: a start date and a number of months to add or subtract.

2. Step 2: Identify missing argument

   The formula =EOMONTH(A1) only has one argument, so Excel returns an error.

3. Final Answer:

   EOMONTH requires two arguments; months argument is missing. -> Option C

4. Quick Check:

   Missing months argument causes error [OK]

Hint: EOMONTH always needs months argument [OK]

Common Mistakes:

• Omitting the months argument
• Assuming one argument works
• Using invalid date formats in A1

5. You want to find the last day of the month three months after the date in cell B2, which contains 2024-11-10. Which formula gives the correct result?

hard

A. =EDATE(B2, 3)

B. =EDATE(B2, -3)

C. =EOMONTH(B2, -3)

D. =EOMONTH(B2, 3)

Solution

1. Step 1: Understand the goal

   You want the last day of the month three months after November 10, 2024, which is 2025-02-29.

2. Step 2: Choose the correct function

   EOMONTH returns the last day of the month after adding months. EDATE returns the same day number, 2025-02-10.

3. Step 3: Calculate the date

   EDATE(B2, 3) returns 2025-02-10; EOMONTH(B2, 3) returns 2025-02-29.

4. Final Answer:

   =EOMONTH(B2, 3) -> Option D

5. Quick Check:

   Last day after 3 months = EOMONTH(B2, 3) [OK]

Hint: Use EOMONTH for last day after months added [OK]

Common Mistakes:

• Using EDATE instead of EOMONTH
• Using negative months when positive needed
• Confusing last day with same day number