Do you need a cable (rogers) box to use a tivo in canada?

Yes, you would need a separate Rogers digital box plus a Tivo Subscription (around $12.95/mth) along with the Tivo box. Your best bet is to get the Rogers PVR instead as it does everything the Tivo does but in a single box. Also it allows you to tape two different digital channels at the same time (the Tivo can only record one digital and one og channel simultaneously).