British Defence Singapore Support Unit (HMNB Singapore)

The British Defence Singapore Support Unit (BDSSU) is a Royal Navy logistics and repair support facility at Sembawang, Singapore, on the northern coast of the island facing the Johor Strait. It is owned by the United Kingdom, operated by Strategic Command under the Director of Overseas Bases, and constitutes the only permanent Royal Navy presence remaining at the former HMNB Singapore. The unit is maintained under the Five Power Defence Arrangements (FPDA) and is manned by Naval Party 1022, a small complement of UK service personnel and civilian contractors numbering in the low tens.

The unit supplies fuel, food, stores, mail and other support to Royal Navy vessels operating in the Indo-Pacific, as well as to warships of the other FPDA navies and the United States Navy. Around 120 vessels a year have called at the facility, placing it among the busiest UK-operated ports for frigate and destroyer movements. Since the May 2021 decision to base River-class offshore patrol vessels permanently in the Indo-Pacific, HMS Tamar and HMS Spey have used the BDSSU as their primary logistics hub, with Type 31 frigates intended to follow. The facility handled the 2018–19 deployments of HMS Sutherland, HMS Albion, HMS Argyll and HMS Montrose, during which it issued more fuel than all naval bases in the United Kingdom combined. It supported elements of UK Carrier Strike Group 21, including RFA Tidespring and the Type 45 destroyer HMS Diamond, and in August 2025 received HMS Dauntless, RFA Tidespring, HMNZS Te Kaha and HMAS Sydney from UK Carrier Strike Group 25. The BDSSU also serves as a staging point for FPDA activity, including Exercise Bersama Lima. Task Force 73, the US Navy logistics group, is based at the same port.

Facilities comprise bulk fuel and stores holdings and repair support; berths accommodate ships up to aircraft carrier size, HMS Illustrious having stored over 500 tonnes of equipment there in 24 hours in November 2013 for humanitarian relief in the Philippines. The remainder of the former base is operated commercially as Sembawang Shipyard.

The site originated as HMNB Singapore, also commissioned as HMS Terror, built by the United Kingdom from 1938 as the basis of the Singapore strategy. British control lapsed between 1942 and 1945. The base was progressively reduced after Singaporean independence and handed over in 1968, with residual facilities retained by the ANZUK grouping and, from 1971, under the FPDA; the BDSSU is the surviving British element of that arrangement.