For most travelers in 2026, you should leave data roaming off unless you have specifically activated an international plan or a travel eSIM. Without a plan, "pay-as-you-go" roaming rates can exceed $2.00 per megabyte, leading to "bill shock" of hundreds of dollars for simply checking your email or using Google Maps. In early 2026, the most cost-effective solution is purchasing a digital eSIM (like Airalo or Holafly), which allows you to get local data rates for as little as $5–$10 for the duration of your trip. Alternatively, major U.S. carriers like T-Mobile often include "free" low-speed international data in their top-tier plans. If you don't have these, turn off "Data Roaming" in your phone's cellular settings and rely on hotel Wi-Fi. Always remember to download offline maps in Google Maps before leaving your home country so you can navigate without using any data at all.