In Excel Online, when you print a worksheet with hidden rows or columns those hidden rows and columns won’t be printed. If you want to include the hidden rows and columns, you’ll need to unhide them before you print the worksheet.
You can tell if rows or columns are hidden either by the missing header labels or by the double lines as shown in this picture.
Here’s how you can unhide rows or columns:
Select the range of headers surrounding the hidden rows or columns. In this example, select all row headers between 2 and 7 to unhide rows 3 and 6.
Right-click the selection and pick Unhide Rows (for columns, pick Unhide Columns).
Click File > Print.
Click Print for a print preview.
In the Print Options box, make sure Entire Sheet is selected, and click Print.
Note: The row and column labels don’t show in print preview and the printout.