Hamatonbetsu is located in northeast Hokkaido; it faces the Sea of Okhotsk to the east where, during the winter, there is drift ice.

Lake Kutcharo designated a Ramsar site in July 1989, and host nearly 300 bird species either year round or as part of the avians' migratory pattern.

Tonbetsu was raised to town status on November 1, 1951 and was renamed Hamatonbetsu due to its coastal location.

Hamatonbetsu has a mayor-council form of government with a directly elected mayor and a unicameral town council of ten members.

In terms of national politics, the town is part of the Hokkaido 12th district of the lower house of the Diet of Japan.

Hamatonbetsu's mascot is Swatton (スワットン) who is a gentle yet clumsy pig dressed as a tundra swan.

According to Ainu legend, he first appeared during the Jomon period to bring food and medical needs for good health and protection from crimes and natural disasters.