From Vava’u, Real Tonga flies to the grassy runways at Niuatoputapu (T$350 one way, weekly) and Niuafo’ou (T$420 one way, fortnightly).
The ferry supposedly makes a trip from Vava’u to Niuatoputapu and Niuafo’ou, then back to Vava’u once a month. Sailings are reliant on unpredictable factors (ie there is no schedule): contact Friendly Islands Shipping Company for info.
Many visitors arrive on private yachts. Both islands are ports of entry to Tonga, but Niuafo’ou lacks a decent anchorage or landing site. Niuatoputapu has a pass in the reef on the northwest side of the island.