U.S. PIRG, The Hidden Cost of
Offshore Tax Havens:
State Budgets Under Pressure
from Tax Loophole Abuse:

Tax havens are countries or jurisdictions
with minimal or no taxes. Corporations
and individuals shift earnings to financial
institutions in these countries to reduce
their U.S. income tax liability—costing
the federal government $150 billion in lost
revenues each year.

Federal taxpayers are not the only victims
of offshore tax havens. Tax havens
deprive state governments of billions of
dollars in badly needed revenues as well.
Based how much income is federally reported
in each state, and on state tax rates,
it is possible to calculate how much each
of the state governments lose as a result of
offshore tax dodging. 

In 2011, states lost approximately
$39.8 billion in tax revenues from corporations
and wealthy individuals who
sheltered money in foreign tax havens.
Multinational corporations account for
more than $26 billion of the lost tax revenue,
and wealthy individuals account
for the rest.