Excel Date Format: change how dates look, and fix dates that won’t change

A date in Excel is a number; the format only decides how it is displayed. Change the look without touching the value.

Steps

1. Select the date cells.
2. Press Ctrl + 1. Number tab › Date.
3. Pick a format from the list. OK.

Custom formats (any layout you want)

Ctrl + 1 › Custom › type a code:

Check it worked

Click the cell. The formula bar shows the date in your system format; the cell shows your chosen look. Both are the same date.

The format will not change

The “dates” are text. Signs: left-aligned, format changes do nothing. Fix:

1. Select the column. Data › Text to Columns › Next › Next.
2. Column data format: Date › choose the order the text is in (DMY for 29/09/2026). Finish.

Or a formula: =DATEVALUE(A1). Details: convert text to date.

Day and month swapped (US vs UK)

Typing 03/04 gives 4 March on an Indian/UK system and 3 April on a US one. To avoid it forever, type 2026-04-03 — Excel reads year-month-day everywhere.