Between September and November 2023, a team of First Nations people and scientist experts conducted a shipboard line-transect survey to address a significant knowledge gap regarding Australian snubfin dolphin (Orcaella heinsohni), Australian humpback dolphin (Sousa sahulensis) and the Indo-Pacific bottlenose dolphin (Tursiops aduncus) in the Northern Great Barrier Reef Marine Park (GBRMP), Queensland, Australia. The survey followed a systematic parallel transect design, with two independent observer platforms. Mark-recapture distance sampling was used to derive abundance estimates and density distribution models. During the 56-day survey period, we completed 3942 km of transect across an area of 20947 km2, from Bloomfield to Cape York. We recorded a total of 23 groups of snubfin dolphins, 60 groups of humpback dolphins and 156 groups of bottlenose dolphins. The resulting population estimates were approximately 600 snubfin dolphins, 1300 humpback dolphins and 5800 bottlenose dolphins. Density distribution models suggest that snubfin dolphins are primarily concentrated near Princess Charlotte Bay, humpback dolphins occurred in five major clusters along the coast, and Indo-Pacific bottlenose dolphins are widely distributed across the region. These results supported the listing of Australian snubfin and humpback dolphins as vulnerable under the EPBC Act list of threatened fauna.