If World War 3 breaks out, men of these ages could be forced to join the UK’s army and fight in Europe.
Pat McFadden discusses prospect of conscription in 2025
The world’s Doomsday Clock has moved closer than ever to midnight. The scientist-run programme is intended to show how close the globe is to nuclear annihilation and as tensions have continued to mount over Iran, Greeland, Venezuela, Israel-Palestine and, of course, Russia-Ukraine, the experts think we’ve never been closer to the end of the world.
And more recently, the UK changed its rules on conscription into the Armed Forces, in a clear signal of preparation for escalation of conflict. The Government recently announced a change to the Army reservists’ rules that increases the age limit from 55 to 65 for call-up to conflicts.
The move is designed to increase the size of the “strategic reserve”, which includes ex-service personnel who are still liable for military service – the “ex-regular reserve” – and a wider “recall reserve” who can be mobilised in dire emergencies. Those in the Army reserves would be the first to be called up or conscripted in wartime.

British people could be forced to join the Army if WW3 breaks out (Image: Getty)
It’s not something anyone particularly wants to think about, but as tensions escalate around the world, there is a possibility that World War 3 could erupt. Just this past summer, the UK government told people to prepare for war on British soil, and is urging better preparedness for conflict across society.
Assuming tensions continue to ramp up and a new global conflict were to erupt, there are some indicators about what would happen if the UK went to war and needed to introduce conscription, or mandatory military service, whether in a WW3 situation or not.
In WW2, conscription began for men aged between 20 to 22 in 1939, up to six months before the war actually broke out.
The UK Parliament website says: “During the spring of 1939 the deteriorating international situation forced the British government under Neville Chamberlain to consider preparations for a possible war against Nazi Germany. Plans for limited conscription applying to single men aged between 20 and 22 were given parliamentary approval in the Military Training Act in May 1939. This required men to undertake six months’ military training, and some 240,000 registered for service.”
But when war was declared, the age range was immediately widened to any man aged 18 to 41.
It continues: “On the day Britain declared war on Germany, 3 September 1939, Parliament immediately passed a more wide-reaching measure. The National Service (Armed Forces) Act imposed conscription on all males aged between 18 and 41 who had to register for service.”
The only men who weren’t called up were those who were too unfit medically, or who worked in vital industries like baking, farming, and medicine, which were vital to the war effort.
It adds: “Those medically unfit were exempted, as were others in key industries and jobs such as baking, farming, medicine, and engineering.”
By the end of 1941, women and ‘all childless widows’ between the ages of 20 and 30 were called up, while men aged up to 51 were called up for military service. Even those aged 52 to 60 were required to take part in “some form of military service”.
With the recent change moving the goalposts on reservists to 65, it’s highly possible that the age range for conscription could be thrown wider than ever before in the face of any potential conflict.
Grant Shapps, the former Defence Secretary, has said that we are “moving from a post-war to a pre-war world”, and General Sir Patrick Sanders, Britain’s most senior Army officer, has called for an increase in the size of the Army and said that the country needs to increase its preparedness for conflict.
A YouGov survey carried out of 3,044 people in late January found that 38% of under-40s said they would refuse to serve in the armed forces if a new world war broke out, and 30% would not serve even if the UK faced ‘imminent invasion’.
The same poll found that 72% supported women being conscripted as well as men.
It isn’t clear what would happen to those refusing to serve in WW3, but in WW2, British ‘conscientious objectors’ were put on trial, with some given mandatory jobs to contribute to the war effort in other ways instead.
