ChatGPT offers a permanent Free plan with basic features available to all...

https://lanesniceblog.scriblorax.com/posts/is-there-a-standard-1-month-chatgpt-plus-free-trial

ChatGPT offers a permanent Free plan with basic features available to all users. Occasionally, targeted promotions provide Plus plan trials, which may require a payment card and auto-renew after the trial ends