If you attempt to merge cells where data is in any other cell, Excel will return the error message, “Merging cells only keeps the upper-left value and discards other values.” In other words, you will lose any data that isn’t in the first cell. If there is data in the cells being merged, Excel will only keep what is in the upper leftmost cell.Data from multiple cells will not be combined when using Merge & Center.

It should be noted that Merge & Center is only a formatting command.The cell alignment may be changed if desired. The result is that both cells now behave like a single cell, which is given center alignment. In the example above, cells A1 and B1 were highlighted then the Merge & Center command was selected. Simply highlight all the cells to be merged, then click the Merge & Center icon. A quick and common way to merge cells is to use the Merge & Center command in the Home tab.