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

https://titusssplendidperspective.almoheet-travel.com/does-chatgpt-plus-include-image-generation-and-how-many-per-day

ChatGPT Plus is listed at $20 per month, but the actual price you pay often varies between $13 and $27. Differences come from taxes like VAT or GST and app store fees on iOS and Android