ChatGPT Plus is listed at $20, but the actual price you pay can range from $13...

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

ChatGPT Plus is listed at $20, but the actual price you pay can range from $13 to $27. This difference is mainly due to taxes like VAT or GST and fees added by app stores, especially on iOS and Android