To unfreeze it entirely it looks like it can take no longer than 3 days. Unfreezing it for specific parties it sounds like is less money and perhaps takes less time but that will depend on the company.

Source: https://www.consumer.ftc.gov/articles/0497-credit-freeze-faq...

Law limits it to no more than three days. My experience has been that it mostly takes place within 12-24 hours.