Based on our assessments, ammonia bunkering will first be introduced in special cases and then well-suited green corridors, before the market possibly matures at a significant size. Two such green corridors are investigated in the paper by AIS data and fuel consumption modelling: Export of iron ore from Western Australia to East Asia as well as container transport from East Asia to North-Western Europe. The current trade of iron ore was found to be from three Pilbara port with about 18,000 voyages in the timeframe 2020 to 2023 with dry bulk ships of about 200,000 DWT. The total transport is more than 800 MTPA (million tonnes per year) to mainly China, South Korea, Japan and Taiwan. It is possible to operate bulk ships on ammonia on this corridor with fueling only in Australia, where a large amount of clean ammonia likely will be produced, and the calculated tank size is 3 000 to 4 500 m3. Bunkering in the other end (China, Taiwan, South Korea, Japan) will reduce the required tank size. Based on the speed ships are sailing on these routes, about 455 ships would be required for this green corridor fully converted to ammonia-fueled ships. It would also require about 10 MTPA ammonia as fuel, which is substantial, but nevertheless still possible in a 2050 perspective. Another possible green corridor is the container trade from East Asia to Europe. It is possible to use ammonia if bunkering of ammonia is available in China/South Korea, Singapore, Egypt and Rotterdam. Tank size of about 6 500 m3 would cover the vast majority of the voyages, and intermediate bunkering would further reduce the tank size.