DOD spent $25B operating bases in 2016

The Defense Department spent $25 billion, or 4% of its annual budget, to operate and support military bases around the world, according to a new Congressional Budget Office report.

CBO found that costs of supporting military bases are strongly related to their size, namely that it would be more cost-effective to expand the population at larger bases than at smaller ones.

"With other base characteristics unchanged, [base operations support] costs associated with an increase in population were lower at larger bases than at smaller bases," CBO states. "For example, in 2016 [base operation support] costs increased by $1,000 for each employee added to bases with 25,000 or more employees, but they increased by $14,000 at bases with 5,000 or fewer employees."

CBO said its analysis also shows that relocating units from larger bases to smaller ones "would generally increase those costs, all other things being equal."

Along with size, CBO analyzed other areas that can impact the cost of supporting a military base such as primary mission, branch of service, location and climate extremes.

"CBO's results could be used to anticipate how BOS costs would change if units were relocated between bases, new units were added, or existing units were disbanded," the report states.