Tehran is 8.5 hours ahead of Ottawa
Best overlap: 8:30 AM to 9:30 AM in Ottawa is 5:00 PM to 6:00 PM in Tehran.
The best time to meet is 8:30 AM to 9:30 AM in Ottawa, which is 5:00 PM to 6:00 PM in Tehran. You've got roughly 1 hour — enough for a focused daily check-in if you hold it at 8:30 AM in Ottawa (5:00 PM in Tehran). The difference isn't constant year-round: Ottawa adjusts for daylight saving while Tehran holds steady.