ChatGPT Plus is listed at $20, but the actual price you pay varies between $13...

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

ChatGPT Plus is listed at $20, but the actual price you pay varies between $13 and $27 depending on where you subscribe. This happens because of taxes like VAT or GST, and extra fees from app stores like Apple or Google