You must set expectations. Tonga's internet infrastructure is satellite-based and fragile (as seen in the 2022 volcano eruption). You will have a 3G/4G signal in the capital, Nuku'alofa, and the main towns. The speed is good enough for WhatsApp, email, and Google Maps, but it is not fast enough for 4K streaming. It is much more reliable than guesthouse Wi-Fi.
Planning the trip? See our Tonga eSIM plans, install in one tap before you fly, and land online. Free VPN included.