5 Pounds Sterling

Tonga issued its own pound-denominated notes from 1921 under direct government authority rather than through a chartered bank — an arrangement unusual for a Pacific territory of this size and one that reflected the kingdom's formal status as a British protectorate, not a colony. The Colonial Bank of Australasia and later the Bank of New Zealand operated on the islands, but neither held the note-issuing privilege.

De La Rue's involvement guaranteed technical quality, but surviving examples of P#4 are genuinely rare. The 1921 series had very limited print runs, and Tonga's small, cash-dependent economy meant notes at the five-pound level circulated hard when they did move.