To do Alt + H A C on Mac in Excel, download and install Accelerator Keys, then press Option, followed by H, A, C.
Command: Align Center
This is how to do Alt + H A C on Mac in Excel with Accelerator Keys, the native ribbon and alt key shortcut solution for Mac users who get more done with Excel.
Alt + H A C horizontally centers cell contents within the cell. Centering is commonly used for column headers and data that looks better centered.