Under defence cuts announced in 2004, RAF Sealand was completely closed in April 2006.

"The degree to which any traces of Dutton's aerodrome survive as sub-surface deposits is currently unknown as there have been no investigative works.

5 FTS RAF Sealand as APOs (Acting Pilot Officers) and upon satisfactory completion of intermediate training became Pilot Officers (POs), and were prepared for posting to a squadron or OTU (Operational Training Unit).

The 30th Air Depot Wing was located at Sealand, but plans were made to relocate it to RAF Brize Norton, both in the UK.

[14] In 2015, the Welsh government agreed to fund a link road to the community so that building could start.

[15][16] In 2019, DECA was granted a new Gate Guardian, to replace the Spitfire with a GR4 Tornado, Tail Number ZA607, due to the long standing relationship that the DECA site has with the Tornado aircraft [17] MOD Sealand is a global repair hub for maintenance, repair, overhaul and upgrade services for the Lockheed Martin F-35 Lightning II aircraft.

[18] In 2023, the DECA was subsumed into the wider Defence Equipment and Support (DE&S) to become DE&S Deca, whose role is dedicated to maintenance, repair, overhaul, upgrade, procurement and managed services provision across Defence electronics, components and general equipment support.

[19] Facilities at MOD Sealand include clean rooms, faraday cages, radar chambers, calibration laboratory, cryptographic facility, storage and warehousing, 3D printing capability, aircraft components bay and cryogenics bay.

Major customers include Ministry of Defence, BAE Systems, Northrop Grumman, General Dynamics, Thales, Rolls Royce, Raytheon, L3 Wescam, United States Department of Defence, Lockheed Martin, MBDA and more.

The ATRC will conduct research in areas such as cybersecurity, software engineering, space, radio frequency, advanced sensing technologies, and next-generation propulsion.

[22] The RAF base lent its name to the 1981 song "Sealand" by Wirral band Orchestral Manoeuvres in the Dark.