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T474 · Tax / GloBE · AINumbers.co

Top-up Tax / QDMTT Calculator

OECD Pillar Two top-up tax per jurisdiction. Top-up tax = (15% − ETR) × GloBE income net SBIE (Art. 5.2.1). Substance-based income exclusion (SBIE) deducted first. Allocates top-up tax across three collection mechanisms: QDMTT (qualified domestic minimum top-up tax, credited against IIR), IIR (income inclusion rule, parent-level), and UTPR (under-taxed profits rule). ⚠ US-HQ groups are exempt from IIR and UTPR per the OECD January 2026 side-by-side package.

OECD Pillar Two GloBE Art. 5.2.1 · Top-up tax QDMTT · IIR · UTPR US-HQ: IIR/UTPR exempt (Jan 2026) Feeds T476 GIR Builder
⚠ US Headquarter Exemption (January 2026): US-headquartered MNE groups are exempt from IIR and UTPR. This tool computes top-up tax for non-US-parented groups and for QDMTT analysis in GloBE-implementing jurisdictions (which affects all groups, including US-parented, where a local QDMTT is enacted). IIR and UTPR columns are greyed out for US-HQ parent. Consult counsel; verify at oecd.org.
ℹ This page takes the substance-based income exclusion (SBIE) as an entered input, from tool 473 or the SBIE calculator; it does not recompute the carve-out. The carve-out rates follow the OECD Article 9.2 transitional schedule: payroll 10 percent falling to 5.8 percent, and tangible assets 8.0 percent falling to 5.4 percent, over fiscal years beginning 2023 through 2032, with 5 percent for both from 2033.
🔒 All inputs are processed locally in your browser. No data is transmitted. Do not enter real personal data — use synthetic or anonymised inputs only.

Parent group configuration

Enter US to apply IIR/UTPR exemption automatically.
Recorded with the result and the exported payload. SBIE is entered, not derived, so the fiscal year does not change the arithmetic.

Jurisdiction inputs (from T473 or manual)

For each jurisdiction: GloBE income (pre-SBIE), covered taxes, SBIE amount (if pre-computed from T473, paste here). Tool recomputes ETR and top-up tax. Check "QDMTT enacted" where a local QDMTT law is in force.

JurisdictionGloBE income (m)Covered taxes (m)SBIE (m)QDMTT enactedQDMTT rate %

Top-up Tax Allocation

Sources: OECD GloBE Model Rules Art. 5.2.1, 5.3, 9.2 (December 2021). QDMTT: Art. 11.3. IIR: Art. 2.1. UTPR: Art. 2.4. US exemption: OECD side-by-side package (January 2026). ⚠ Verify enacted QDMTT jurisdictions and current transitional safe harbour status. This tool produces indicative estimates only. Consult a qualified tax adviser before filing.