ChatGPT Plus has a listed price of $20 but the actual cost you pay can vary...

https://www.save-bookmarks.win/chatgpt-plus-is-listed-at-20-but-the-actual-price-you-pay-varies-between-13

ChatGPT Plus has a listed price of $20 but the actual cost you pay can vary between $13 and $27. This difference comes from taxes like VAT or GST and extra fees added by app stores on iOS and Android