df['Fruit Total']= df.iloc[:, -4:-1].sum(axis=1) print (df) Apples Bananas Grapes Kiwis Fruit Total 0 2.0 3.0 NaN 1.0 5.0 1 1.0 3.0 7.0 NaN 11.0 2 NaN NaN 2.0 3.0 2.0