The Armed Forces are thousands of personnel short of requirements, figures show.
Despite improvements in recruitment and retention in recent years, the three services need 4,460 extra men and women between them to hit their target levels.
Latest manpower statistics from the Ministry of Defence (MoD) revealed the combined strength of the Army, Naval Service and Royal Air Force to be 174,010 - only 97.5% of the 178,470 required.
However, that was up from the 96.8% last summer and the MoD stressed fewer people were leaving and more joining the forces.
It said the number of trained personnel who had left in the past year was down by 15.7%, while recruitment was up by 8.7%, year-on-year.
The Army had the biggest shortfall in manpower, of 1,960, although it also has by far the biggest staff of the three services.
The RAF was 1,620 down on its target level and the Navy was 880 short, according to the figures, which described the position on July 1.
Defence minister Kevan Jones said growing numbers of people wanted to make a career in the forces.
"The Armed Forces offer a challenging and financially rewarding career," he said.
"Each and every recruit will help to work as part of the international community to support the Afghan people as they build a better future."
