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

https://suprmind.ai/hub/chatgpt/pricing/chatgpt-plus-price/

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