Was Fogg rich?
Yes, Phileas Fogg was rich.
Was Phileas Fogg rich? Undoubtedly. But those who knew him best could not imagine how he had made his fortune, and Mr. Fogg was the last person to whom to apply for the information.
The above quote comes from the first chapter. What's interesting about Fogg and his wealth is that nobody knows where the wealth comes from. The paragraphs preceding the above quote explain that Fogg was never seen in the banking district, or at the docks, or at an office, or the courts. He's not a scientist either, so it is mystery where his wealth comes from. But there is no doubt that he is wealthy. It is known that he has an open credit line with the Barings and that "his cheques were regularly paid" from "flush accounts."
Additionally, he lives in a mansion on Saville Row, and Fogg only dines on the best that the club can offer.
When he breakfasted or dined all the resources of the club—its kitchens and pantries, its buttery and dairy—aided to crowd his table with their most succulent stores; he was served by the gravest waiters, in dress coats, and shoes with swan-skin soles, who proffered the viands in special porcelain, and on the finest linen; club decanters, of a lost mould, contained his sherry, his port, and his cinnamon-spiced claret; while his beverages were refreshingly cooled with ice, brought at great cost from the American lakes.
Fogg also has a full time servant. That's a privilege for the wealthy. Lastly, the reader knows that he is wealthy because he casually bets 20,000 pounds that he can circumnavigate the globe in 80 days or less.