The move brings to an end the building and testing of six Type 45 destroyers which have each been launched on Glasgow's river during a construction programme that has spanned the last 13 years.
The £6billlion programme to produce one of the world's deadliest fleets, to replace the aging Type 42s, generated hundreds of jobs at the Scotstoun and Govan yards which are owned by BAE Systems.
But the defence conglomerate's contractual obligations have come to an end when the Royal Navy took full responsibility for the last of the fleet several months ahead of schedule.
The announcement was made by defence minister Philip Dunne, who said: "Thanks to the skill and hard work of the commanding officer, the ship's company and their MoD and industry partners, HMS Duncan has entered service four months early.
Duncan is the only Type 45 to be officially affiliated to Glasgow.
It was anchored at the city's King George V docks on it's first official visit to Glasgow last month.
It will now spend the following year on a series of sea trials.