ChatGPT Plus is listed at $20 per month, but the actual price you pay can range...

https://dibz.me/blog/is-there-a-chatgpt-plus-free-trial-i-can-click-to-start-1223

ChatGPT Plus is listed at $20 per month, but the actual price you pay can range from about $13 to $27. This happens because of extra taxes like VAT or GST depending on where you live, and app stores like Apple’s or Google’s add their own fees