If your business has funds it can go without for a few months or even years, it might be an interesting idea to invest that money in a time deposit account. A time deposit account is a relatively safe investment (unless the bank where the account is managed goes bankrupt). You are entitled to get back what you put in when the account reaches maturity and the interest rate stays the same the whole time. 

However, you need to be aware that your cash surpluses remain tied up for the entire term of the investment. In other words, your assets cannot be accessed until the maturity date.

This depends mainly on how long you can go without your cash surplus. If you invest your cash in a time deposit account, you will not have access to it for a preset period of time. Fortunately, KBC Brussels has a wide range of time deposit accounts on offer, which ensures you can choose the investment whose term is best suited to your needs. If, for instance, you opt for an investment of 0-3 months, you won't have to do without your money for too long, but the interest earned will of course be lower than what you would get from a long-term investment. Therefore, it's best to weigh up what's important to you.