11 Best International Roaming Plans Compared for 2025

9. Local prepaid SIMs (airport and local shops)

Buying a local prepaid SIM after you land often gives the cheapest per-GB rates and best local speeds. Airports such as Mumbai, Delhi, JFK, or Heathrow usually have kiosks that sell starter packs with preset data and calling allowances; activation may require showing ID and can be completed at the kiosk or with vendor help. The upside is clear savings on heavy usage like streaming and map navigation. The downside is you’ll get a local number, which may complicate two-factor authentication tied to your home number unless you keep your original SIM active via dual‑SIM or eSIM. Top practical tip: keep a small guide ready with APN settings and vendor contacts, and load digital wallet or UPI equivalents as needed when recharging in India. Pros: lowest cost per GB, best local performance. Cons: new phone number, paperwork in some countries. Best for: long stays or data-heavy trips where saving on data matters most.