In B1: =LEFT(A1,3)&"-"&MID(A1,4,2)&"-"&RIGHT(A1,3)
Copy down
Since the numbers in col A are text,
we can put in say, C1: =A1+0
then format C1 as Custom: 000-00-000
and copy C1 down
For both ways, the assumptions that the data posted & desired
transformation
is representative down the col applies. If it's not, it won't work.
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