National debt interest and entitlement spending push FY2026 federal budget deficit toward $2 trillion

• Net interest on the national debt rose $98 billion (13% increase) due to debt growth and higher long-term interest rates, making it the largest category of increased spending
• Social Security, Medicare, and Medicaid spending combined increased by $169 billion, driven by higher enrollment, increased benefits, and rising healthcare costs per enrollee
• Tariff revenues initially rose $55 billion (51% increase) from Trump administration policies, but refunds following a February court ruling reduced tariff revenues by approximately $70 billion in May and June

Summary: U.S. Federal Budget Deficit Approaches $2 Trillion in FY2026

The Congressional Budget Office (CBO) reported that the FY2026 federal budget deficit reached $1.373 trillion through the first nine months of the fiscal year, representing a $35 billion increase over the same period last year. The deficit is projected to approach or exceed $2 trillion by year-end.

Key Drivers:

Federal spending increased $178 billion year-over-year, outpacing tax revenue growth of $142 billion. The primary spending increases include:

• Net interest on national debt: Up $98 billion (13%), driven by the growing $39 trillion+ national debt and elevated long-term interest rates
• Social Security: Increased $62 billion (5%) due to higher average benefits and more beneficiaries
• Medicare: Rose $58 billion (8%) from higher enrollment and payment rates
• Medicaid: Up $49 billion (10%) due to rising costs per enrollee

Revenue Developments:

Tax receipts grew primarily from individual income and payroll taxes, up $169 billion (5%). Customs duties surged $55 billion (51%) due to President Trump's tariffs, though a February court ruling resulted in approximately $70 billion in tariff refunds paid in May and June, significantly reducing this revenue source.

Market Implications:

Experts warn this deficit level is unsustainable during economic expansion with low unemployment. The Committee for a Responsible Federal Budget notes Social Security and Medicare trust funds face exhaustion within seven years, triggering automatic benefit cuts unless Congress acts. The organization recommends targeting a more sustainable 3% deficit-to-GDP ratio and establishing a bipartisan fiscal commission to address entitlement spending and long-term budget sustainability.