FY2026-2035 · CBO February 2026 baseline

AMT: Extend TCJA Relief

Extend TCJA's higher AMT exemptions ($88K single, $137K MFJ) past 2025. CRS/CBO put the 10-year cost at ~$1.36T.

Ten-year deficit effect, conventional+$450.5Badds to the deficit

With macroeconomic feedback and debt service+$506.9BFRB/US-Lite (Federal Reserve calibrated)

Checked against

Published score +$1,357.1B; this estimate is 66.8% away (unfitted reconstruction). Unfitted reconstruction, 66.8% from $1.36T (CRS R48286 Table 1 (transcribing CBO 60114/…) — no constant is fitted to this figure.

No out-of-sample band: no pre-registered row scores an AMT reform. The 44 pre-registered Tier 1 rows are the only tier that measures this model's accuracy, and none of them scores a policy of this kind.

Year by year

billions, conventional

Fiscal year	Revenue	Deficit, conventional	Macro feedback	Debt service	Deficit, dynamic
2026	-$39.3B	+$39.3B	+$6.8B	+$1.6B	+$34.0B
2027	-$40.5B	+$40.5B	+$7.9B	+$3.2B	+$35.8B
2028	-$41.7B	+$41.7B	+$6.8B	+$4.9B	+$39.7B
2029	-$42.9B	+$42.9B	+$5.3B	+$6.6B	+$44.2B
2030	-$44.2B	+$44.2B	+$3.9B	+$8.3B	+$48.7B
2031	-$45.6B	+$45.6B	+$2.8B	+$10.2B	+$52.9B
2032	-$46.9B	+$46.9B	+$1.9B	+$12.0B	+$57.0B
2033	-$48.3B	+$48.3B	+$1.3B	+$14.0B	+$61.0B
2034	-$49.8B	+$49.8B	+$0.9B	+$16.0B	+$64.8B
2035	-$51.3B	+$51.3B	+$0.6B	+$18.0B	+$68.7B

Download CSV

Who pays

first year, by income group

The distribution engine cannot yet represent this kind of policy household by household (for example estate tax, tariffs, international or enforcement provisions). An all-zero table would look flat and be wrong, so none is shown.

Economic effects

difference from the CBO baseline

GDP, summed over the window+0.55percent-years

Jobs at the largest effect+72K

Deficit effect of the GDP change-$38.3Bmore tax collected

Deficit effect of interest on the debt+$94.7Bmore debt, more interest

Fiscal year	GDP level	Jobs	Unemployment	10-year rate	GDP change, deficit	Interest, deficit
2026	+0.098%	+63K	-0.05 pt	+0.00 pt	-$6.8B	+$1.6B
2027	+0.112%	+72K	-0.06 pt	+0.01 pt	-$7.9B	+$3.2B
2028	+0.098%	+62K	-0.05 pt	+0.01 pt	-$6.8B	+$4.9B
2029	+0.076%	+49K	-0.04 pt	+0.02 pt	-$5.3B	+$6.6B
2030	+0.056%	+36K	-0.03 pt	+0.02 pt	-$3.9B	+$8.3B
2031	+0.040%	+25K	-0.02 pt	+0.03 pt	-$2.8B	+$10.2B
2032	+0.028%	+18K	-0.01 pt	+0.03 pt	-$1.9B	+$12.0B
2033	+0.019%	+12K	-0.01 pt	+0.04 pt	-$1.3B	+$14.0B
2034	+0.013%	+8K	-0.01 pt	+0.04 pt	-$0.9B	+$16.0B
2035	+0.009%	+6K	-0.00 pt	+0.05 pt	-$0.6B	+$18.0B

FRB/US-Lite (Federal Reserve calibrated). Demand effects fade over five to seven years as monetary policy responds; there is no supply-side channel. The dynamic score is the conventional score, plus the deficit effects of the GDP change and of interest on the debt: +$450.5B - $38.3B + $94.7B = +$506.9B.

Other scoring models

exploratory

Model	Ten-year deficit effect	Method
CBO-Style	+$450.5B	Static + ETI behavioral response + optional FRB/US dynamic feedback
TPC-Microsim Pilot	Cannot score this	Extend TCJA AMT Relief (AMTPolicy) does not map onto current microsim pilot reforms (income-tax rates, CTC, EITC, SALT, std deduction, AMT exemption).

No pilot model returned distributional output; the comparison is aggregate-only.

CBO-Style is the model behind the headline above. The TPC-style microsimulation is a pilot: where the two disagree, the gap tells you how much the answer depends on method. It is not an official range.

Limitations

holdout labels follow the locked post-2026-05-02 regression protocol; they are not retroactive historical out-of-sample claims.
No pre-registered out-of-sample row scores a policy of this class, so this model's accuracy on one has not been measured.
Poor against the corrected target by construction, and the gap is the point of correcting it: the fitted annual scores $450.5B against a published $1,357.1B (-66.8%). Retuning the constant to close that is forbidden — it would re-fit the module to the number it is being tested on.
The module's structural (derived) path scores $855.3B, -37.0% against the same row, so the unfitted machinery is about 1.8x closer to the document than the fitted constant. See planning/lanes/PROVENANCE_amt_insulin.md.
Definitional gap, not split: CRS/CBO score the AMT provision inside a full TCJA-extension package, where extended rate cuts push more filers into AMT than a standalone AMT extension would. TPC's T25-0049 reconstructs the standalone counterfactual and implies roughly $855B; both are published and they answer different questions.

Cite asWilse-Samson, Laurence. “AMT: Extend TCJA Relief.” Fiscal Policy Calculator, CBO February 2026 baseline, FY2026-2035. https://fiscal.lwilsesamson.com/explore/amt-extend-tcja-relief