There are no specific numbers that always win in bingo. The numbers are drawn randomly, so every number has an equal chance of being called.
According to a study published by Play OJO, one of the UK's bingo operators, they found that the number six is the most called number. The next one is followed by four. This applies to any match, including online bingo games. These numbers are often called for a game of chance despite the game relying on luck.