I had reason to check this out. Yes, easy to search-engine it. But here it is anyhow:
TOLL FREE AREA CODES
800 833 844 855 866 877 888
WHAT HAPPENED TO 811 AND 822?
Area code 822 is expected to be used in the future, followed by 880 through 887, then 889. However, 811 is reserved as a three-digit number for various other purposes. In addition, 899 is reserved as a member of the series x9x for future numbering plan expansion.
Just to satisfy your yet-to-be-curious curiosity.
You're welcome.