The Ministry of Defence (MoD) said that 1,000 soldiers and 1,600 Royal Navy personnel would be laid off.
It is expected that around half the army redundancies will be compulsory.
Following a review on October, the MoD said it would reduce the number of military personnel by 17,000 over four years: 7,000 from the army and 5,000 each from the Royal Navy and the Royal Air Force (RAF).
It expected to have to make 11,000 redundancies.
Britain has 178,470 active troops, with 102,600 in the army, 35,480 in the navy and 40,390 in the RAF, according to the International Institute for Strategic Studies. Prime Minister David Cameron's coalition government is imposing eight percent defence spending cuts as it tries to get Britain's record deficit under control.
It also reviewed the configuration of Britain's armed forces to shift the focus towards modern-day engagements such as in Iraq and Afghanistan rather than the Cold War era.
"We have to ensure that our armed forces are best struc