Go into the table in 'design' view. Click on the credit card field number.
'Field Size' in the bottom half of the screen is probably 'long integer'?
You probably want it to be at least 'Single'.
Single is limited to about 7 digits, Double to 14.
A Credit Card Number isn't a *number* in the sense that you'll never
want to do calculations with it. It should be stored in a Text field,
not any kind of number field.
The OP was asking about Excel, not Access, in any case.
John W. Vinson[MVP]