The NHL's department of player safety announced the suspension Monday, a day after the player delivered the check in the third period of Buffalo's 3-2 shootout loss at New York.
Kaleta was assessed a major penalty for boarding and a game misconduct. The league took into account that Richards was shaken up, but returned. The league also noted Kaleta had been suspended twice before in his career.
Kaleta will lose more than $72,000 in salary, and begin serving the suspension Tuesday, when Buffalo plays at Carolina.
He's not eligible to return until March 17, when Buffalo plays at Washington.