accordance, according to, in accordance to, in accordance with

The phrases according to and in accordance with refer to agreement or conformity with an authority, rules or procedures. In accordance to is non-standard English.

• In accordance with National Hockey League regulations, the player was given a three-game suspension for slashing.
• According to the Farmers’ Almanac, it will be sunny this week; according to the long-term weather report, it will be dry; and according to the ache in my arthritic joints, it will rain.
• Incorrect usage:
  The chemical company acted in accordance to the new environmental regulations.
• Correct usage:
  The chemical company acted in accordance with . . .