Welcome to the Forum Martyn!
Save the CSV as a .xlsx file. With both files open, you can use a formula with VLOOKUP or possible combination of INDEX/MATCH in your export file to look up the new price for same SKU in your customer's file.
In your export file, let's say the SKU is in column A and the first row of data is in row 2.
In the Customer file let's say the SKU is in column A, and the price is in column B.
In your export file, select the cell in the first row of data, in the column where you want the new price to appear.
Type
Formula:
=VLOOKUP(A2,2,
Now, without hitting ENTER, go to the customer's file and highlight columns A and B, the entire columns. Now return to your export file, and your formula should look something like this
Formula:
=VLOOKUP(A2,2,'[Customer File.xlsx]Sheet1'!$A:$B
Keep typing and hit ENTER:
Formula:
=VLOOKUP(A2,2,'[Customer File.xlsx]Sheet1'!$A:$B,FALSE)
Now copy the formula down to row 5400.
To get the actual formulas that will work with your files, provide the specifics of file name and where the data is located.
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