The Australian actor, who quit the soap two years ago to enjoy his retirement, recently announced that he is returning to the role of Harold Bishop in order to make some more money.
Smith told TV Week magazine: "I sound a bit stupid saying this, but... part of the reason [I came back] was because I'm rather fond of Harold."
He also admitted that he spent tens of thousands of dollars from his retirement nest egg while he wasn't working, adding: "It's that awful thing of being retired, so any money I lost on my superannuation was really affecting me."
Smith said that he and wife Gail's financial situation has not become too "tough" because he had been "wise enough to spread stuff around". "But it did stop retirement from being very comfortable," he added.
Earlier this month, the star said that his character returns to Ramsay Street to "help a friend".