ChatGPT Plus has a $20 list price, but the actual cost you pay can range from...

https://www.slideserve.com/aaron_ward92/why-does-chatgpt-plus-cost-more-on-android-than-on-the-web

ChatGPT Plus has a $20 list price, but the actual cost you pay can range from about $13 to $27. This difference happens because of local taxes like VAT or GST and fees added by app stores like Apple or Google