Turkish Airlines: Often operates nonstop or one-stop flights between Houston (IAH) and Istanbul (IST), known for competitive economy seating, complimentary meal service on long-haul flights, and robust connectivity across Turkey and beyond. United Airlines: May offer codeshare or partner connections to IST via European hubs; expect solid loyalty program benefits for Star Alliance members and widely available one-stop routings. Other carriers (Lufthansa, British Airways, KLM) commonly provide one-stop itineraries via major European hubs with varying seat comfort and carry-on policies. For March travel, compare total travel time, seat pitch, Wi-Fi availability, and included baggage allowances — sometimes paying slightly more for a nonstop on Turkish Airlines is worth the time savings. CTA: Compare March fares and baggage policies among carriers flying IAH to ISTA to pick the best fit for your trip.