For international travelers in 2026, the cheapest entry points into the UK are almost always London, Manchester, and London Stansted/Luton. London Gatwick and Heathrow offer the most competition, which often drives down prices for transatlantic or long-haul flights. If you are flying from within Europe, budget carriers like Ryanair and easyJet make London Stansted and London Luton incredibly cheap, sometimes with fares under £20. Outside of London, Manchester (MAN) is a major hub for northern England and often undercuts London prices for flights from the Middle East and Asia. Edinburgh (EDI) is the most affordable gateway to Scotland, while Birmingham (BHX) serves as a cost-effective alternative for the Midlands. Pro-tip: check flights into "secondary" airports like Bristol (BRS) or Glasgow (GLA), as they occasionally offer regional deals that beat the major hubs if you book at least 6 weeks in advance.