Tax administrations’ perceptions of the behaviour of the Big Four professional services firms ­- Deloitte, EY, KPMG, PwC - on tax matters shows a lack of trust, warns the OECD, although there were positive views about their willingness to follow the letter of the law and formal compliance. However, there were less positive impressions of whether they actually followed the spirit of tax laws.

The findings of the first OECD in-depth report into the relationship between tax authorities, multinationals and the Big Four, highlight poor communication and low levels of trust with tax officials, while complaints about the complexity of tax law added to the lack of transparency.