Basic references
Another sheet: =Sheet2!A1; another workbook: =[Book2.xlsx]Sheet1!A1. Quote sheet names that contain spaces.
3-D references
=SUM(Sheet1:Sheet12!B2) sums the same cell across consecutive sheets — ideal for monthly sheets, since new sheets inside the range count automatically.
Consolidate
- Data → Consolidate;
- Add each range and choose sum, average or count;
- Tick Top row and Left column to match by label.
Careful
Cross-workbook links break when files move; merge into one workbook for long-term maintenance.