São Paulo is 2 hours ahead of Ottawa
Best overlap: 8:00 AM to 4:00 PM in Ottawa is 10:00 AM to 6:00 PM in São Paulo.
Shoot for 8:00 AM to 4:00 PM in Ottawa; your São Paulo colleagues will see that as 10:00 AM to 6:00 PM. The overlap is wide at 8 hours, so you can protect mornings for deep work and still find plenty of meeting time. Don't be caught out by clock changes — Ottawa observes daylight saving and São Paulo doesn't, so the offset varies by an hour through the year.