Boosting

Boosting means making an account's rating, the number used to estimate competitive playing level, or its results rise artificially instead of earning them through normal competitive games. A clear example is arranging in advance for an opponent to lose so the winning account receives rating points. Lichess also treats knowingly playing an opponent who is intentionally deflating their rating in order to benefit the other player as boosting.

The key is not that a rating rises quickly, but that the increase is manufactured. A legitimate winning streak, even against stronger opponents, is not boosting. The problem begins when the result no longer reflects genuine competition because of coordination, manipulated accounts, or fixed games.

Boosting can be an outcome of collusion, meaning deliberate cooperation between participants to deceive others or manipulate a competition. It is also the conceptual opposite of sandbagging, where someone deliberately lowers a rating. Anti-cheating policies commonly treat both as forms of result or rating manipulation, although platforms do not always use exactly the same labels.