While debit cards are not the most convenient option for depositing funds in American online casinos, learn more here they are widely accepted. MasterCard debit cards are accepted by virtually all reliable online casinos. To deposit funds with a debit card, simply choose the MasterCard Debit option in the payment options menu. Within minutes, the funds should be in your account. Another advantage of using a debit card is that you only spend the money you have. If you ever decide to withdraw money, the amount is immediately deducted from your balance