HMS H7 was a British H-class submarine built by the Canadian Vickers Co, Montreal, Quebec, Canada.

It had a complement of twenty-two crew members, a length of 171 feet (52 m), and a surfaced range of 1,600 nautical miles (3,000 km; 1,800 mi) at 10 knots (19 km/h; 12 mph).

British H-class submarines had ranges of 1,600 nautical miles (3,000 km; 1,800 mi) at speeds of 10 knots (19 km/h; 12 mph).

[1] H7 was fitted with a 6 pounds (2.7 kg) Hotchkiss quick-firing gun (6-pounder) and four 18 inches (460 mm) torpedo tubes.

[1] It is a Holland 602 type submarine but was designed to meet Royal Navy specifications.