Dallas is 1 hour behind Ottawa
Best overlap: 9:00 AM to 6:00 PM in Ottawa is 8:00 AM to 5:00 PM in Dallas.
Plan around 9:00 AM to 6:00 PM in Ottawa, which is 8:00 AM to 5:00 PM in Dallas, to catch everyone during office hours. Dallas is 1 hour behind Ottawa, but with 9 hours of common ground you can hold morning or afternoon meetings without anyone working odd hours.