Excel allows us to easily combine date and time through the use of simple arithmetic operations and some formatting adjustments. This article provides a step-by-step tutorial on how to add date and time.

*Figure 1. Final result: How to** add date and time*

**Date and time**

Date has a different format as time. To add time to a date, we must first understand how date and time are managed in Excel. When we enter a date in a cell, say 16/05/2019, the date will be displayed with a pre-set format such as this:

*Figure 2. Date in pre-set format*

We might wonder, what is the default time of a date when we enter it on a cell? To find out, let us change the format of the cell such that both the date and time are displayed.

- Enter the date in B4
- Select the cell and press
**Ctrl + 1**to launch thedialog box*Format Cells* - In Format Cells, select
tab >*Number*>*Custom**dd/mm/yyyy h:mm*

*Figure 3. Format Cells dialog box*

Cell B4 is now displaying the date and time for the date we have entered. As shown below, the default time for a date is 0:00 or 12 midnight. This is key to understanding how to add date and time.

*Figure 4. Date in custom format showing the time*

**How to add date and time?**

**Add cell references**

Suppose we have a date in one cell and a time in another cell. In order to add date and time, we simply enter the cell reference of date, a plus sign “+” for addition, then the cell reference for time. For example, we enter the formula =B3+C3 in cell E3.

*Figure 5. Output: **Add date and time*

Column E shows the result when we add date and time using cell references.

**Add hours to date**

Excel has a unique way of storing time, wherein one day has the value “1”. Since there are 24 hours in a day, one hour is expressed as 1/24. Hence, when we want to add hours to a date, we divide the hours by 24, then add the resulting value to the date.

For example, we want to add 3 hours to the date in B3. We enter the formula in E3:

`=B3+C3/24`

*Figure 6. Output: **Add hours to date*

Column E shows that we have successfully added the date and time in columns B and C. In row 5, we want to add 24 hours to a date. 24 hours is equivalent to one day. Using our formula, we have obtained the result in E5, 17/05/2019, which is one day after the date 16/05/2019.