Excel's precision for numbers is 15 significant digits.
You can enter your credit card number as text by either formatting the cell
as text before entering the number or by preceding the number with a ',
which will not show.

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Kind regards,

Niek Otten

Microsoft MVP - Excel

"Jaxz24" wrote in message
...
I am trying to enter a 16 digit credit card number into an excel
spreadsheet.
For some reason however excel is truncating the last numerial and
replacing
it with a '0'. It displays 15 digit numbers fine. Why is this and how do i
fix it? (ive tried cell formatting but to no avail)