Most of the online casinos will require a minimum deposit in order to withdraw your winnings from a no deposit bonus. In many cases, the minimum deposit is as low as $1, but you should check with the casino. There are a few online casinos that do not require a deposit.
There are two reasons why the casinos require new players to make a deposit in order to withdraw any free bonus winnings. First, they want to verify that you are of legal age to gamble within the online casino, and that you have the ability to make a deposit and play at the casino if you choose to do so in the future. Second, they want to protect themselves from bonus abuse. Over the years, many people have signed up for bonuses with no intentions of playing the casino games or making a deposit. The abusers were only interested in getting the free money. By requiring a deposit, they reduce the risk that abusers will try to take advantage of the bonuses that they are offering to their players.