How to Add Hours and Minutes to a Time in Excel

To add hours to a time in Excel, add a fraction of a day: =A2+TIME(3,30,0) adds 3 hours 30 minutes, and =A2+B2/24 adds the number of hours in B2. Both work because Excel stores time as part of a day, so one hour is 1/24. This guide shows how to add hours and minutes, how to handle shifts that end after midnight, and why the result sometimes looks like a decimal or a row of #### signs.

How Excel stores time (and why /24 works)#

Excel stores every time as a fraction of one day. Midnight is 0, noon is 0.5 and 6:00 PM is 0.75. Dates work the same way, as whole numbers, which the date basics lesson explains.

So to add hours, you convert them into this fraction first. Adding a plain 3 adds three days, not three hours. That is the most common mistake.

The examples use this shift list. Start is a real time, and Hours is a plain number:

How to add hours to a time with TIME#

Use the TIME function when the amount is fixed. TIME takes hours, minutes and seconds and returns them as a fraction of a day:

=B2+TIME(3,30,0)

With 9:15 in B2, the result is 12:45. To add exactly 2 hours, write =B2+TIME(2,0,0). TIME works in every version of Excel and is easy to read: anyone can see you added 3 hours and 30 minutes.

If the result shows as a decimal, such as 0.53125, the cell has a number format. Apply a time format with Ctrl+Shift+@, or open Format Cells (Windows: Ctrl+1; Mac: ⌘1), choose Time, and pick 13:30 or 1:30 PM.

How to add hours stored as a number#

Divide by 24 when the hours are a number in another cell, such as a shift length of 7.5. In D2:

=B2+C2/24

Priya starts at 9:15 and works 7.5 hours, so the result is 16:45. Fill the formula down (Windows: Ctrl+D; Mac: ⌘D) to get Daniel's 16:15 and Omar's 19:30. Decimal hours are common in timesheets, because 7.5 is easier to type and total than 7:30. See how to build a timesheet in Excel for the full layout.

If the amount is already a time value, such as a duration of 2:15 in C2, just add the two cells: =B2+C2. No conversion is needed, because both are already fractions of a day.

How to add minutes or seconds#

Use the same idea with a different divisor. There are 1,440 minutes and 86,400 seconds in a day:

To see seconds, use a format such as h:mm:ss. Without it, Excel still stores the seconds but hides them.

How to add hours past midnight#

A time that passes midnight goes above 1, which is the next day. Grace starts at 22:00 and works 8 hours:

=B5+C5/24

The value is 1.25: one whole day plus 0.25 (6:00 AM). With a normal time format, Excel shows 6:00, because time formats hide whole days. That looks right, but the hidden extra day causes trouble when you later subtract or compare times.

For a clean clock time between 0:00 and 23:59, wrap the formula in MOD:

=MOD(B5+C5/24,1)

MOD with 1 keeps only the part after the decimal point, so the value is exactly 0.25, or 6:00. The shift schedule guide uses this for night shifts.

If the cell holds a date and time, such as 2 Nov 2026 22:00, a plain addition is better: the result becomes 3 Nov 2026 6:00, and the date moves forward on its own. For adding whole days, months or years, see how to add days, months and years to a date.

How to subtract hours from a time#

Subtract the same way: =B2-TIME(2,0,0) or =B2-C2/24. With 9:15 in B2, =B2-TIME(2,0,0) returns 7:15.

If the result would go before midnight, such as 1:00 minus 3 hours, Excel gets a negative number. A negative time can't be shown, so the cell fills with #####. MOD fixes this too:

=MOD(B2-3/24,1)

With 1:00 in B2, this returns 22:00. To find the gap between two times rather than shift one, use subtraction of two times, as covered in how to calculate time difference in Excel.

Why your result looks wrong#

Most problems come from formats, text, or the TIME function's limits:

1. A decimal instead of a time. The value is right; the format isn't. Apply a time format.
2. The answer is days off. You added a whole number. Use /24 or TIME.
3. TIME ignores whole days. The hour argument wraps after 23, so TIME(27,0,0) is 3:00, not 27 hours. For large amounts, use 27/24.
4. #VALUE! or no change. The start time is text, often from an export or a CSV file. Convert it with VALUE(B2), or check alignment: text sits on the left of the cell by default.
5. A total above 24 hours shows too little. A format like h:mm resets at 24. Use [h]:mm for totals, for example when you add up overtime hours.
6. ##### in the cell. Either the column is too narrow or the time is negative. Widen it, or use MOD.

Practise it#

Time maths only clicks once you've typed it a few times. Practise how Excel stores dates in a live spreadsheet: the same "everything is a number" idea is behind adding hours. If formulas are still new to you, start with your first formulas. Each lesson checks your work instantly. Then try the exercise on this page, where you turn a text start time and a shift length into an end time.