One of the most widespread Nepenthes species, N. ampullaria is native to Borneo, the Maluku Islands, New Guinea, Peninsular Malaysia, Singapore, Sumatra, and Thailand [REF].
In Sumatra and Peninsular Malaysia, it grows from sea-level to 1100 m altitude on flat terrain in heath forest, padang (meaning "field" in Malay), belukar, peat swamp forest, degraded swamp forest, and in padi fields [REF].