When working with dates in Excel, there might be situations where you need to determine the first Monday of a given month. Excel provides various functions that allow us to calculate this dynamically. In this article, we will explore different formulas to find the first Monday of a month and apply them to the months of 2025.
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1. Finding the First Monday of Any Month
You can use one of the following formulas to find the first Monday of any month based on a given date in cell A2
.
Method 1: Using the 8th Day of the Month
=DATE(YEAR(A2), MONTH(A2), 8) - WEEKDAY(DATE(YEAR(A2), MONTH(A2), 6))
Explanation:
DATE(YEAR(A2), MONTH(A2), 8)
: Generates the 8th day of the month, which ensures that the first Monday has already passed.WEEKDAY(DATE(YEAR(A2), MONTH(A2), 6))
: Determines the weekday number of the 6th day of the month.- Subtracting the
WEEKDAY
value from the 8th day gives us the first Monday.
Method 2: Using the 7th Day of the Month
=DATE(YEAR(A2), MONTH(A2), 7) - WEEKDAY(DATE(YEAR(A2), MONTH(A2), 7), 3)
Explanation:
DATE(YEAR(A2), MONTH(A2), 7)
: Generates the 7th day of the month.WEEKDAY(DATE(YEAR(A2), MONTH(A2), 7), 3)
: Returns the weekday position of the 7th, where Monday = 0.- Subtracting this value from the 7th gives the first Monday of the month.
Example for 2025:
Month | First Day | First Monday |
January | 2025-01-01 | 2025-06-01 |
February | 2025-02-01 | 2025-03-02 |
March | 2025-01-03 | 2025-03-03 |
April | 2025-01-04 | 2025-07-04 |
May | 2025-01-05 | 2025-05-05 |
June | 2025-01-06 | 2025-02-06 |
July | 2025-01-07 | 2025-07-07 |
August | 2025-01-08 | 2025-04-08 |
September | 2025-01-09 | 2025-01-09 |
October | 2025-01-10 | 2025-06-10 |
November | 2025-01-11 | 2025-03-11 |
December | 2025-01-12 | 2025-01-12 |
2. Find the First Monday of the Current Month
If you want to find the first Monday of the current month dynamically, use:
=DATE(YEAR(TODAY()), MONTH(TODAY()), 1) + CHOOSE(WEEKDAY(DATE(YEAR(TODAY()), MONTH(TODAY()), 1)), 1, 0, 6, 5, 4, 3, 2)
Explanation:
TODAY()
: Returns the current date.YEAR(TODAY())
andMONTH(TODAY())
: Extracts the current year and month.- The rest of the formula works similarly to the first formula, adjusting the first day of the month to the nearest Monday.
This formula updates automatically every month based on the system date.
3. Applications of Determining the First Monday in Excel
Determining the first Monday of each month in Excel is not just a calculation technique but also has several practical applications in work and time management. Below are specific applications along with detailed instructions.
Here’s a detailed explanation of each formula and how they work in Excel:
3.1 Work Planning: Determining the First Monday for Scheduling Meetings
Many businesses schedule important meetings on the first Monday of the month to set work plans in advance. Accurately determining the first Monday helps organize schedules efficiently and avoid conflicts.
Formula Used:
=DATE(YEAR(A2), MONTH(A2), 1) + CHOOSE(WEEKDAY(DATE(YEAR(A2), MONTH(A2), 1)), 1, 0, 6, 5, 4, 3, 2)
Where A2
contains any date within the target month.
Breaking Down the Formula:
DATE(YEAR(A2), MONTH(A2), 1)
- Extracts the year and month from
A2
and sets the day to1
, effectively giving the first day of that month. - Example: If
A2 = 15/03/2025
, this returns01/03/2025
.
WEEKDAY(DATE(YEAR(A2), MONTH(A2), 1))
- Determines the weekday number of the first day of the month.
- Excel assigns numbers to weekdays as follows:
- 1 = Sunday, 2 = Monday, …, 7 = Saturday.
- Example: If
01/03/2025
(March 1, 2025) falls on a Saturday,WEEKDAY()
returns7
.
CHOOSE(WEEKDAY(...), 1, 0, 6, 5, 4, 3, 2)
Adjusts the first day of the month to find the first Monday.
This function returns an offset (number of days to add) based on the weekday of the first day:
- If it’s Sunday (1) → Add 1 day → (Monday)
- If it’s Monday (2) → Add 0 days → (Already Monday)
- If it’s Tuesday (3) → Add 6 days
- If it’s Wednesday (4) → Add 5 days
- If it’s Thursday (5) → Add 4 days
- If it’s Friday (6) → Add 3 days
- If it’s Saturday (7) → Add 2 days
Final Calculation: The formula returns the first Monday of the given month by adding the appropriate offset to the first day.
3.2 Monthly Reporting: Calculating the Reporting Date
In accounting and project management, many reports are generated on a fixed day of the month, such as the first Monday.
How to Implement:
Use the same formula as above to find the first Monday.
Apply Conditional Formatting in Excel to highlight the reporting date automatically.
Use an IF
function to check if a given date matches the first Monday.
Formula to Check if a Date is the First Monday:
=IF(B2=DATE(YEAR(B2), MONTH(B2), 1) + CHOOSE(WEEKDAY(DATE(YEAR(B2), MONTH(B2), 1)), 1, 0, 6, 5, 4, 3, 2), "Report Day", "")
Where B2
contains the date to check.
Breaking Down the Formula:
- The formula finds the first Monday of the month (as explained in 3.1).
- It then compares
B2
with this calculated first Monday. - If they are the same, it returns
"Report Day"
, otherwise, it leaves the cell blank.
3.3 Remembering Important Events: Setting Reminders or Scheduling
Determining the first Monday is useful for personal management, such as setting bill payment reminders, medical checkups, or other recurring events.
How to Implement:
- Use the formula to find the first Monday.
- Combine it with Excel notification features like:
- Conditional Formatting to highlight the date.
- VBA macros to generate alerts.
- Outlook Calendar integration to set reminders.
VBA Code for an Automatic Reminder:
Sub EventReminder()
Dim ReminderDate As Date
ReminderDate = DateSerial(Year(Date), Month(Date), 1) + Choose(Weekday(DateSerial(Year(Date), Month(Date), 1)), 1, 0, 6, 5, 4, 3, 2)
MsgBox "Important event on: " & ReminderDate, vbInformation, "Reminder"
End Sub
Breaking Down the Code:
Dim ReminderDate As Date
→ Declares a variable to store the first Monday.
DateSerial(Year(Date), Month(Date), 1)
Retrieves the first day of the current month.
Choose(WEEKDAY(...), 1, 0, 6, 5, 4, 3, 2)
Finds the first Monday (same logic as in 3.1).
MsgBox "Important event on: " & ReminderDate
Displays a pop-up with the first Monday date.
How It Works:
- Running this macro will show a pop-up message with the first Monday of the current month.
- This can be extended to trigger email reminders or create calendar events.
Conclusion
Using these formulas, you can quickly determine the first Monday of any month, whether it’s a fixed date or dynamically based on the current month. These techniques are helpful for setting up schedules, work plans, and reminders in Excel.
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