The substantial headroom created by the July 2025 One Big Beautiful Bill Act, which raised the statutory debt limit by $5 trillion to $41.1 trillion, forms the core driver of trader consensus against a U.S. default by the end of 2027. Current debt subject to the limit stands well below that ceiling, with projections from the Bipartisan Policy Center and Congressional Budget Office indicating it will most likely bind sometime between late winter and mid-summer 2027. Treasury extraordinary measures would then extend runway by an additional six to nine months before any payment interruption. Congress has repeatedly raised or suspended the limit ahead of binding constraints in prior cycles, reflecting institutional incentives to avoid the severe market, economic, and credit-rating disruptions that would follow a default on authorized obligations. Scenarios that could still shift odds include an unusually prolonged 2027 impasse driven by partisan disagreement over accompanying fiscal measures, or a sharp deterioration in revenue collections from an unforeseen downturn.