To engage meaningfully in the budget process, legislatures require reliable, unbiased information to support evidence-based policymaking. Parliamentary budget offices (PBOs) are independent public institutions established under the statutory authority of the legislature to provide objective analysis of public finances. Analysis provided by these institutions supports and strengthens parliamentary budget oversight, helping to address the capacity asymmetry between the legislature and the executive. They undertake tasks such as conducting independent analyses of government spending proposals and of underlying macroeconomic and fiscal assumptions, thereby contributing to fiscal transparency and accountability. PBOs can also promote fiscal transparency and public understanding by making fiscal data more accessible for both the legislature and the public.
PBOs are a type of independent fiscal institution (IFI). PBOs are the predominant IFI model in SEA countries, whereas in OECD countries, fiscal councils – typically focused on monitoring fiscal policy, assessing compliance with fiscal rules, and promoting fiscal sustainability and transparency – are more common. In 2024, four out of eight SEA countries for which data are available had a PBO, and the remaining four SEA countries had no plans to establish one. Only one of these, Cambodia, has established a PBO since 2020. In contrast, the number of IFIs in OECD countries has grown markedly since the global financial crisis, with 35 national institutions now operating in 29 of the 38 Member countries. Among these, ten operate as PBOs. Of the four OECD countries in the Asia-Pacific region, Australia and Korea have established PBOs (Figure 3.4).
The three SEA PBOs for which data are available (Cambodia, the Philippines, Thailand) fulfil some of the core functions of a PBO, in that they provide budget analysis to the legislature and respond to parliamentary requests (Table 3.10). However, only two of the three SEA PBOs independently initiate and publish analysis, as recommended in the OECD Principles for IFIs (OECD, 2014). In contrast, all OECD IFIs fulfil this requirement. Two out of three SEA PBOs for which data are available contribute to forecasting accuracy by assessing macroeconomic and fiscal projections and providing non-binding public opinions. This role is also more widespread among OECD IFIs, of whom 33 out of 35 IFIs have a role in relation to macroeconomic forecasts, and 31 out of 35 IFIs have a role in relation to fiscal forecasts. Moreover, no SEA PBO conducts long-term fiscal sustainability analysis. This function is carried out by 25 out of 35 OECD IFIs, including Australia and Korea. This indicates room to expand the analytical capacity of SEA PBOs to support budget oversight.
