Traders assign an 82.5% implied probability against another US sovereign credit rating downgrade before 2027 primarily because the major agencies have affirmed existing ratings with stable outlooks following Moody’s May 2025 move to Aa1 and Fitch’s 2023 reduction to AA+. Recent affirmations, including Fitch’s August 2025 confirmation of AA+ with a stable outlook, reflect assessments that fiscal pressures from the $39 trillion debt level and ongoing deficits have not escalated to the point of triggering further action in the near term. Congressional Budget Office projections of continued borrowing have been priced in without prompting negative outlooks, and no new debt-ceiling confrontations or governance shocks have materialized since the 2025 adjustments. This consensus aligns with historical patterns where agencies typically require sustained deterioration or major policy shifts before revising ratings again within such a compressed window.