[1] Tinnanbar is bounded by the Great Sandy Strait on the north and east and by Kauri Creek to the south.

The town is located on the north coast, while the east coastal strip is protected as the Great Sandy Conservation Park.

[10] The Great Sandy Marine Park along the Tinnanbar coast is a "go-slow" area for boats to avoid injury to turtles and dugongs and protect the natural environment.

In a "no-slow" area speeds may not exceed 6 knots (11 km/h; 6.9 mph) and motorised sports activities are prohibited.

However, there is a transit channel from the Tinnanbar boat ramp to beyond the marine park where the go-slow rules do not apply.