Privates Stephen Milam, 25, Henry Bulbeck, 19, and Richard Gawn, 29, and permanent staff instructor Sgt Major (Warrant Officer) Shaun Towers will mobilise on April 1 and, after special training for the role, will deploy to Afghanistan in June for a four-month tour of duty.
Commanding Officer, Lieut Col Patrick Crowley, said: "This deployment will put the 3rd Battalion firmly on the map because it's the first operational tour that the regiment's TA battalion has had since World War II. We've been used to providing individuals for overseas operations but not formed bodies of men, so this is something totally different and unique.
"This is a rare opportunity that's being embraced by my soldiers and at the moment we have more potential volunteers than the 43 we need for the large platoon required. The response has been fantastic and they are extremely enthusiastic."
The local TA volunteers are currently negotiating with their employers for leave of absence from their civilian jobs for six months. They will receive the same rates of pay and be subject to the same regulations as members of the Regular Army.
The volunteers will provide security as the guard and protection force at Afghanistan's key Bagram Airport and their tasks will include patrolling.
The 3rd Battalion is part of the Shorncliffe, Kent-based Infantry Brigade, whose Commander, Brigadier David Santa-Olalla, said: "The Afghanistan deployment emphasises the relevance of the modern Territorial Army.
"It is in addition to our current campaign to recruit Territorial Army soldiers for the new Civil Contingencies Reaction Force to help deal with emergencies in the UK and together these are two key operational roles that the TA has not had before.
"We very much hope that employers will give their full backing to any of their employees who are serving in the TA and are earmarked to serve in Afghanistan. It's a role of national and international importance, and they will be playing a part in helping to stabilise a very unstable country."
Brigadier Santa-Olalla added: "Each individual will gain a great many skills which will put them in good stead for years to come and which are enormously valuable to their employers in the civilian workplace as well as the military one."
Pte Milam lives in Woking where he works for Fox Garage as a motor vehicle technician. He said: "My employer has always been supportive of my TA service, understands that we've got a job to do and is 100 per cent behind me. My job will be there when I get back.
"I jumped at the chance to serve in Afghanistan and do my bit for the country. It's great to be going there as a unit with my friends and I just can't wait to get out there and do the job. It will be the experience of a lifetime."
Pte Bulbeck lives in Long Sutton, near Bentley, and until volunteering for Afghanistan worked for Boots as a laboratory technician. Pte Gawn, lives in Staines and in civilian life is in management consultancy.