This paper looks at estimates of the potential gains from taxing across borders, alongside largely domestic measures such as property tax, personal income tax, VAT, and tobacco taxes. It finds that while action on cross-border taxation could yield additional tax take in the region of one percent of GDP, in many countries measures targeting the domestic tax base might deliver something in the region of nine percent. The main enabler is political commitment.
Domestic measures have greater potential for raising tax yields over time. Rough estimates indicate that there may be $9 of additional tax capacity from domestic policy measures for every $1 from international action. The main enabler is political commitment.