Much has been said and written about the ‘fiscal behaviour’ of multinationals. A tax code of conduct is often mentioned as a 'catch-all solution' for stimulating 'acceptable fiscal behaviour'. Stakeholders increasingly demand fiscal accountability to obtain verifiable and validated credible tax information. A tax code of conduct without a proper public reporting strategy will not build trust with stakeholders as it cannot offer the necessary guarantees that the (guiding) principles as prescribed are indeed followed. Credibility is created through accountability. Accountability can only be provided through transparency: showing how a corporate fiscal policy has translated itself into effective actions that have been monitored by the company or external auditors. A Tax code of conduct without a reporting obligation will not provide confidence to stakeholders like investors and civil society. A serious tax transparency strategy will and moreover contribute to combat 'greenwashing'. We address existing Tax Codes of Conduct, company examples and the new global tax reporting standard GRI 207: Tax 2019.