The listed ChatGPT Plus price is $20 per month, but the actual charge can vary...

https://wiki-triod.win/index.php/What_Do_You_Get_with_ChatGPT_Plus_in_2026%3F

The listed ChatGPT Plus price is $20 per month, but the actual charge can vary from about $13 to $27 depending on where you subscribe. This happens because taxes like VAT or GST and extra fees added by app stores affect the final cost