Washington DC and Atlanta are on the same time. Both cities use Eastern Time (EST/EDT, UTC-5/-4). When it's 12:00 PM in Washington DC, it's also 12:00 PM in Atlanta.
Both cities observe daylight saving time on the same schedule, keeping them synchronized year-round.
Any time works! Since both cities share the same time zone, you can call during normal business hours (9:00 AM - 6:00 PM) without any conversion needed.
Washington DC and Atlanta are both major East Coast cities with significant political and business connections. The Acela corridor connects them, and flights take about 1.5 hours.