The ChatGPT Plus subscription lists at $20, but your actual cost can range from...

https://mill-wiki.win/index.php/ChatGPT_Plus_File_Upload_Limit_Per_Message:_Is_It_10_Files%3F

The ChatGPT Plus subscription lists at $20, but your actual cost can range from about $13 to $27. This difference comes from extra charges like VAT, GST, or fees added by app stores like Apple and Google