While there is no allocated keyboard shortcut to Merge cells in Google Sheets, we can achieve this task by using the toolbar method.
1. Highlight the Cells you want to Merge
Left Click on one of the cells you want to merge then hold down the left mouse key and drag across to the next cell highlighting them both.
For vertical selections, repeat this step but drag the cursor downwards.
2. Click on the Merge Cells Icon in the Toolbar
On the toolbar there is a ‘Merge Cells’ option, click this to begin the process.
While the Merge Cells tool operates intuitively based on what has been selected, there is a dropdown menu available via an arrow just to the right of the Merge icon that will give you the option to select a horizontal or vertical cell merger.
3. Click OK on the Content Loss Warning Message
By merging cells, the information that is in the top-leftmost cell will be all that is retained by the spreadsheet. The data in the cell(s) to the right will be lost.
You will receive the following warning when clicking the Merge Cell function. Make sure that all information you wish to retain is backed up before clicking ’OK’ on this message.