The advertised ChatGPT Plus price is $20, but what you actually pay can range...

https://smoothdecorator.com/why-did-openai-keep-chatgpt-plus-at-20-since-february-2023/

The advertised ChatGPT Plus price is $20, but what you actually pay can range from about $13 to $27. This difference comes from factors like regional taxes (VAT or GST) and extra fees added by app stores