Excel Comma Separated Column Values
Join the values of an Excel column into one comma separated string using a simple running formula.
To turn a column of values into a single comma separated list, build the string up row by row.
Put these formulas in column B, next to values in column A:
text
B2 = A1 & ", " & A2
B3 = B2 & ", " & A3
Then copy the formula in B3 down the rest of the cells. Each row adds the next value to the string from the row above, so the last cell in column B holds the full list.
Example
If A1 to A3 hold red, green and blue, then B3 shows red, green, blue.