A banking bonus might sound like something you get from your local bank, but it's really another part of the arsenal of tools that online casinos have to get players to behave in ways they'd like. In this case, it's a way to persuade players to use specific deposit or withdrawal methods, sometimes collectively called banking methods. A banking bonus is often offered on top of other bonuses, making it a great way to have some bonus credits added to your account for something you may have done anyway.
The primary reason for an online casino to offer a banking bonus is to get players to use options other than credit cards. This could be simply a way to promote new payment transfer options or because of a desire to handle less credit card traffic (possibly because of fees charged by the credit card companies). Whatever the case, the casino then offers the banking bonus as an extra incentive, along with any other applicable bonus.
As an example, let's say Casino X has a 100 percent match on intial deposits up to $200 for new players, plus an extra 10 percent match of that deposit is made with Neteller. If you deposit the full $200 with a credit card, you'll get $200 in bonus credits. But if you make that same deposit with Netller, you'll end up with $220 in bonus credits.
A banking bonus could be attached to other kinds of bonuses too, like monthly or special seasonal offers. In all cases, banking bonuses need to be cleared like other bonuses by using the credits to make wagers in casino games. Once the bonus is clear, any credits remaining can usually be cashed out in the same way as normal credits.
Banking bonuses should definitely be a part of your thought process when deciding how to deposit money, but they may not be enough to cancel out other negatives. If the banking bonus is offered often enough to cancel out the fees, it becomes a good deal and one you should consider if everything else (speed, reliability, etc.) is equal.