Houston to Sydney (Mascot) (IAH–SYD) — Airlines, Schedules & Connections

US passport holders must obtain an Electronic Travel Authority (ETA) before boarding. Apply through the Australian ETA app (subclass 601). The ETA costs AUD 20, is valid for 12 months with multiple entries, and allows stays of up to 90 days per visit. Processing is usually instant. Passport must be valid for at least 6 months beyond the date of entry.

IAH has no direct rail link to downtown Houston. The IAH Express bus runs from Houston Amtrak/Greyhound station via Park & Ride to Terminal C (60–90 min, $1.25 with METRO Q card). This is the only transit option; Houston's rail network does not reach the airport.Taxis from downtown Houston cost $50–70 and take 40–60 minutes. Ride-hails (Uber, Lyft) are typically $35–55. IAH sits 23 miles north of downtown on the North Freeway (I-45); traffic is heavy during morning and evening rush. Remote economy parking lots serve all terminals via shuttle.

Airport Link trains depart every 10 minutes to Central Station (13 min, AUD $20.10 with Opal). The station access fee makes this more expensive than typical Sydney transit. Taxis from International Terminal queue outside arrivals; metered fares to the CBD run AUD $45–65. Uber operates from a designated ride-share zone.Rental car companies have desks in both the international and domestic terminal precincts. A SkyBus operates to the CBD and several suburbs as a cheaper alternative to taxis (AUD $24–27).

Temperate oceanic climate. Summers (December–February) are warm and humid at 24–32°C with afternoon sea breezes and occasional severe thunderstorms that can cause extended ground stops. Winters (June–August) are mild and mostly dry at 8–17°C. Fog on winter mornings occasionally delays operations.

The airport faces its greatest disruption risk from summer thunderstorms and, less commonly, from east-coast lows bringing heavy rain and strong winds in autumn and winter. Pack layers for winter. Summer evenings can be surprisingly cool with sea breezes.