ChatGPT Plus lists at $20 a month but actual costs vary by country and device....

https://www.play-bookmarks.win/chatgpt-plus-costs-20-per-month-before-taxes-the-final-price-changes

ChatGPT Plus lists at $20 a month but actual costs vary by country and device. That’s because taxes like VAT or GST get added, and app stores charge extra fees too. So, buying through an app can cost more than on the web