Underutilised forest tree species are attracting interest to increase food security of smallholders. However, tree nut commercialisation requires understanding kernel size and identifying trees that produce large nuts. This study explored kernel attributes of two forest nut species, Terminalia catappa and Barringtonia spp. Specifically, we measured kernel weight and kernel-to-fruit ratio collected from Fiji, Solomon Islands and Vanuatu. Significant tree to tree variations in kernel weight and kernel to fruit ratio of all three nut trees were found across countries. High kernel to fruit ratio can result in a higher financial return. The average kernel weight for Barringtonia spp. was 9.6, 7.6 and 5.6 g in Solomon Island, Vanuatu and Fiji, respectively. The average kernel to fruit ratios were 8.5% (0.5-28.9%) for Barringtonia spp. in Fiji, 16.2% (0.5-29.5%) in Solomon Islands and 12.5% (2.5-29.4%) in Vanuatu. The kernel weight of T. catappa was 1.7, 1.5 and 0.3 g in Solomon Island, Vanuatu and Fiji, respectively. T. catappa had the average kernel to fruit ratio of 4.7% in Fiji, 5.6% in Solomon Islands and 5.6% in Vanuatu. Both Barringtonia spp. and T. catappa have a high potential to be commercialised.