How to set cell background color in OpenPyXL

In order to set a cell’s background color in OpenPyXL, use PatternFill with fill_type="solid" and start_color="your_desired_color" and no end_color. The following example will set a cell’s background to green:

sheet["A1"].fill = PatternFill("solid", start_color="5cb800")

Full example based on our OpenPyXL minimal XLSX write example

from openpyxl import Workbook
wb = Workbook()
sheet = wb["Sheet"] # This sheet is created by default
# Add content to sheet
sheet["A1"] = "This is cell A1"
sheet["A1"].fill = PatternFill("solid", start_color="5cb800")
# Save
wb.save("openpyxl-test.xlsx")