If cell A1 contains 123, in cell B1 type ="ab"&A1. Copy down the entire
column. Then select column B, do a Copy and then Paste Special, Value.

"Riza" wrote:

I have like 5000 different data and I need to add letter ab in front of them.
Could anyone tell me how to do this.

for example 123 is what it says but I need ab123 and each row is different
number.