In an opinion piece in Het Financieele Dagblad (FD), Van Schaik warns that the current reporting method focuses on cash payments. This means an expenditure is recorded when money is paid, rather than when military equipment is delivered or a country’s operational capacity increases. That distinction matters, he writes. A country that makes a large advance payment for weapons may report higher defence spending immediately, even if the equipment will not arrive for several years. Meanwhile, another country may appear to spend less while receiving equipment ordered earlier.

Van Schaik also points to military pensions. NATO currently counts pension payments to veterans as defence expenditure. These payments can increase a country’s reported defence budget without directly improving the readiness or deployability of its armed forces. The issue becomes more significant under NATO’s proposed 5% target, which includes 3.5% for defence spending and 1.5% for broader security-related investments. At that level, the target could substantially influence national budget choices, Van Schaik argues.

Reflecting operational capabilities

He does not call for replacing cash-based reporting. Instead, he proposes complementing it with information on outstanding investment commitments, delivered but unpaid equipment, advance payments, inventories and pension obligations. He also calls for clearer rules on which activities may be classified as defence spending, such as border security, cybersecurity and support for Ukraine. According to Van Schaik, this additional transparency would show whether higher defence budgets genuinely translate into greater operational capability, rather than reflecting accounting choices alone.