By grounding policy decisions in solid evidence, countries can better navigate the complexities of tax reforms and ensure that their strategies effectively support the financing of the SDGs. Administrative data and ex-ante policy modelling, such as tax-benefit microsimulation modelling, are indispensable in providing a full picture to policymakers. Data and modelling infrastructure should be public goods accessible to the government and its agencies, academia, think tanks and CSOs to enable an inclusive debate about the choices governments face when making decisions on tax and benefit policies.