Congress enacted the Terrorism Risk Insurance Act (TRIA) in 2002, in response to terrorism insurance becoming unavailable or, when offered, extremely costly in the wake of the 9/11 attacks. The law creates an incentive for a functioning private terrorism insurance market by providing a government reinsurance backstop for catastrophic terrorist attack losses. Extended first in 2005 and again in 2007, TRIA is set to expire at the end of 2014, and Congress is again considering the appropriate government role in terrorism insurance markets. This policy brief examines the potential federal spending implications of allowing TRIA to expire. Combining information on federal spending through TRIA, the influence of TRIA on the availability of terrorism insurance coverage, and the relationship between uninsured losses and federal disaster assistance spending, the authors find that, in the absence of a terrorist attack, TRIA costs taxpayers relatively little, and in the event of a terrorist attack comparable to any experienced before, it is expected to save taxpayers money.