Why and how the PBO rounds its estimates of the financial implications of policy proposals.

Learn about our approach to determining the behavioural assumptions we apply when estimating the cost of policy proposals.

How public debt interest (PDI) is treated in PBO costings.

Parliamentarians and parties must be involved in any costing activity for policies attributed to them.

PBO costings don't include the possible impact of any provisions in the Contingency Reserve.

How and when broader economy‑wide effects, also referred to as second round effects, are captured in policy costings.

Learn about the factors affecting uncertainty in costings and how the PBO deals with them.

Information for Commonwealth agencies who work with the PBO.