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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.
🔒 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.
Affects SBIE transitional rates.

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, 9.1 (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.