For years the Social Security surplus made the federal deficit look smaller — through 10 months of fiscal 2026 the off-budget accounts added $116 billion to it instead

The Monthly Treasury Statement, the government's official monthly books, does something the headline deficit figure hides: it splits the budget in two. Most of the government is on-budget. Two entities are off-budget by law — the Social Security trust funds and the Postal Service. We pulled Treasury's on-budget and off-budget lines for the first 10 months of each fiscal year back to 2022. Through July 31, 2026 — 10 months into fiscal 2026 — the off-budget accounts took in $1.126 trillion and spent $1.242 trillion, a deficit of $116.1 billion. Off-budget receipts are essentially Social Security's payroll taxes; the outlays are its benefit checks plus the Postal Service's net operations. The accounts spent about $1.10 for every $1.00 they received. That is a reversal. In the same 10-month window, the off-budget balance ran a surplus of roughly $6 billion in fiscal 2022 and $15 billion in fiscal 2023, then crossed into deficit — minus $17.7 billion in 2024, minus $80.8 billion in 2025, and minus $116.1 billion in 2026. The shortfall widened about 44% in the past year alone. The off-budget deficit is 6.5% of the government's total $1.799 trillion deficit through July; the on-budget side accounts for the other 93.5%, or $1.683 trillion. The two halves reconcile exactly to the headline year-to-date deficit Treasury reports.

The following is analysis, not fact. The unified deficit is, by definition, the on-budget balance plus the off-budget balance. So the sign of the off-budget line does real work: when it ran a surplus, it was subtracted from the reported deficit, making the total look smaller than the on-budget government alone; now that it is negative, it adds. Across this five-year window that offset flipped from shrinking the headline number to enlarging it. One precision the raw line hides: this is a cash gap, not a measure of Social Security's reserves. Treasury's off-budget receipts line counts payroll and related social-insurance taxes only — it does not include the interest the trust funds earn on their holdings of special-issue Treasury securities. That intragovernmental interest is credited to the funds outside this cash line, so the change in the funds' reserves is smaller than the $116 billion operating gap ^mmodeled. The $116 billion is the operating gap between what came in from workers and what went out in benefits, not the change in the funds' balance — which these MTS cash lines do not themselves measure. The on-budget side still dwarfs all of this. The finding is not that Social Security and the Post Office drive the deficit — they do not, at 6.5% of it. It is that the part of the budget that used to offset the deficit no longer does, and in this window has begun to add to it ^mmodeled.

Three honest caveats. First, off-budget is not Social Security alone: the line bundles the Postal Service, which runs its own persistent losses, so it overstates a Social-Security-only figure on the outlay side. Second, the cash framing cuts against alarm — counting the interest the trust funds also receive, the programs' total income ran closer to balance than the minus $116 billion cash line suggests, and the accumulated reserves have not been exhausted. Third, this is a 10-month snapshot; the calendar timing of benefit payments and payroll-tax receipts moves the monthly figures, and the full-year number will differ from the year-to-date one.

Read one way, this looks like a milestone: the combined off-budget operating cash balance — Social Security's payroll taxes and benefits plus the Postal Service — has flipped from surplus to deficit, which budget analysts have long forecast as the demographic turn arrives ^mmodeled. What has disappeared in this window is that operating cash surplus, not the trust funds' total income or accumulated reserves, which counting interest still cushions. Read the other way, it is partly an artifact of where a line is drawn — the same dollars would land in the deficit whether Social Security were counted on-budget or off, and once its interest income is counted the program sits nearer to balance than the cash gap implies. Both readings rest on the same set of Treasury lines.