The squadron mainly conducts troop carrying, load-lifting, and maritime interdiction missions but can also perform CASEVAC and deployed SAR duties.

845 NAS formed on 1 January 1943, at USNAS Quonset Point, as a Torpedo Bomber Reconnaissance Squadron (TBRS) flying the new Grumman Avenger, designed as a much needed replacement for the ageing Fairey Swordfish.

For the following year, the squadron saw action over Malaya, Ceylon, and Sumatra before being disbanded in 1945.845 reformed on 15 March 1955, at Gosport to be an Anti Submarine unit flying the newly proved Westland Whirlwind HAS.22's, with which it saw service on several ships in the Mediterranean and Indonesia.

For its part in this long and difficult operation, the squadron was awarded the Boyd Trophy for the Navy's most outstanding piece of aviation in the year.

While embarked aboard Albion later that year, the ship was ordered to make best speed for Singapore to help quell the rebellion in Brunei and the subsequent Indonesian inspired insurrection.

After a few quiet years involving exercises all round the globe and the inclusion of Lieutenant The Prince of Wales (now King Charles III) in Red Dragon flight, the Ministry of Defence announced that a permanent presence was to be established in Northern Ireland, which resulted in a six weeks rolling roulement for all commando aircrew.

In November 1971, the squadron prepared to abandon ship and evacuate Bulwark when a serious boiler room fire broke out while off the coast of (then) Jugoslavia.

After initially being tasked with resupplying the convoy while passing the Ascension Islands, the squadron inserted SAS troops into South Georgia, which preceded its recapture.

845 received its Merlin Helicopters from the former 28 (Army Cooperation) Squadron RAF in July 2015[10] and participated in Exercise Black Alligator from mid-August to early October 2015.

Embarked in RFA Argus the squadron spent eight months in the region to provide support to British Overseas Territories during the hurricane season, whilst also working in conjunction with the United States Coastguard in counter narcotic operations.

During B Flight’s tenure in the area the squadron, alongside the United States Military, provided disaster relief to Honduras in the wake of Hurricanes Eta and Iota that hit in late November.

From September to December 2022, B Flight embarked in RFA Argus alongside 847 Naval Air Squadron for Littoral Response Group South (LRG(S)).

The task group provided a sustained presence and reassurance whilst working with numerous NATO partners and regional allies in the Mediterranean and North Africa.

Whilst on Exercise Lion Strike in Montenegro, personnel from the squadron happened across a stray puppy which they sought to adopt and bring back to the UK.

Through social media campaigning the squadron raised over £6000 and began the processes to bring ‘KT’ the puppy (named after her love for cable ties) home.