Planning for a class of vessels to replace the fifteen Fremantle-class patrol boats began in 1993 as a joint project with the Royal Malaysian Navy, but was cancelled when Malaysia pulled out of the process.

The Armidales are longer and heavier than their Fremantle-class predecessors, with improved seakeeping ability and increased range, allowing them to reach Australia's offshore territories.

DMS's contract to provide in-service support was terminated in 2017, and the patrol boats underwent a major refit in Singapore to reinforce the hull.

A fictional Armidale-class boat, HMAS Hammersley, appears in the Australian military drama series Sea Patrol from the second season onwards, with filming occurring aboard multiple ships of the class.

[3] The cost of maintaining the ageing vessels prompted the Department of Defence to create the Replacement Patrol Boat program, which received the procurement project designation SEA 1444.

Instead of specifying a number of vessels, the coverage of 3,000 ship-days per year (with 1,800 to be spent on border protection operations, and a surge capability of 3,600 days) was given, with the producer to determine how many ships were needed to meet this.

[6] Australian Defence Industries (ADI) tendered a design based on the Royal Danish Navy's Flyvefisken-class patrol vessel.

[1] The ship is designed to a combination of Det Norske Veritas standards for high-speed light craft and RAN requirements: much effort went into avoiding attempts to overengineer the Armidales or turn them into 'miniature warships'.

[1] The Armidales can travel at a maximum speed of 25 knots (46 km/h; 29 mph), and are driven by two propeller shafts, each connected to an MTU 4000 16V diesel engine, providing 6,225 horsepower (4,642 kW).

[1][9] The main armament of the Armidale class is a Rafael Typhoon stabilised 25-millimetre (0.98 in) gun mount fitted with an M242 Bushmaster autocannon.

[1][13] Each RHIB has a dedicated cradle and davit, the boats can be launched and recovered easily, and a centralised 'dressing room' incorporated into the ship's design has streamlined the deployment and return of personnel.

[1] Personnel have access to e-mail and satellite television, and the galley is better equipped than that on a Fremantle-class vessel and better suited to use in heavy seas.

[1] The comfort of personnel is also significantly improved over the Fremantles, with air conditioning throughout the entire ship (excluding engine and machinery compartments).

Since June 2005, all active Armidales have undergone operating restrictions on two occasions, both due to water contamination of the main fuel systems.

[2][16] In 2010, allegations were made to The Australian that a sailor working in the austere compartment on a different vessel had been gassed with hydrogen sulphide, and carbon monoxide was regularly detected in the enclosed space.

[18] In response, the Department of Defence threatened to cancel DMS' maintenance contract based on the company's poor performance in maintaining the Armidale's (but did not go ahead due to the political repercussions from potentially losing local jobs).

[19] The patrol boat fleet began a mid-life refit program in October 2015, in order to extend hull life until a replacement class of larger vessels enters service from 2022.

At the start of 2014, the long transit differences and near-constant deployment of the patrol boats for Operation Resolute was impacting on the ability to keep the vessels properly maintained.

[16] In August 2014, a fire broke out aboard Bundaberg while undergoing refit work at a civilian shipyard in Hemmant, Queensland.

[33][34] These vessels, with a theoretical maximum displacement up to 2,000 tonnes, would use a modular mission payload system to change between roles as required, and would be equipped for helicopter or unmanned aerial vehicle operations.