Federal Individual Income Tax
Deterministic composition for us/fiit at 2026-01. Outputs: regular_tax_before_credits, income_tax_before_refundable_credits, eitc, ctc_after_advance_payments, alternative_minimum_tax, income_tax_before_credits. Corpus: unversioned corpus.
us-fiit · period 2026-01 · 137 rules · 78 parameters · spec @ 733d1a17920a
Entities
primary: TaxUnit · members: Person · relations: dependent_of_tax_unit→Person, ctc_qualifying_child_of_tax_unit→Person, exemption_individual_of_tax_unit→Person, senior_deduction_individual_of_tax_unit→Person, living_apart_child_of_tax_unit→Person, qualifying_child_of_tax_unit→Person
Certified outputs (+131 more encoded rules readable via lookup_value)
regular_tax_before_creditsTaxUnitscalar · USD · Yearacknowledged incomplete
26 USC 1(h), 1(j), and 55(c)
ctc_after_advance_paymentsTaxUnitscalar · USD · Yearacknowledged incomplete
26 USC 24(j)(1)
income_tax_before_refundable_creditsTaxUnitscalar · USD · Yearprimaryacknowledged incomplete
26 USC 26(a), 26 USC 1411, and other federal income-tax additions
eitcTaxUnitscalar · USD · Yearacknowledged incomplete
26 USC 32(a), 32(c)(1)(E), 32(i), 32(k)
alternative_minimum_taxTaxUnitscalar · USD · Yearacknowledged incomplete
26 USC 55(a), 55(b)(1)(A)
income_tax_before_creditsTaxUnitscalar · USD · Yearacknowledged incomplete
26 USC 1 and 55(a)
Input slots
Person (53)
age: decimal = 0
certain_noncitizen_exception_applies: bool = false
child_principal_abode_fraction_of_taxable_year: decimal = 0
child_resided_with_both_parents_same_amount_of_time_and_taxpayer_parent_has_highest_adjusted_gross_income: bool = false
child_resided_with_taxpayer_parent_for_longest_period: bool = false
ctc_child_deduction_allowed: bool = false
ctc_child_missing_identification: bool = false
ctc_child_satisfies_dependency_rules: bool = false
ctc_child_satisfies_subsection_c: bool = false
ctc_person_satisfies_dependency_rules: bool = false
election_made_for_foreign_earned_income: bool = false
election_made_for_housing_cost_amount: bool = false
filing_status: integer = 0 {1=income_tax_bracket_thresholds_joint, 2=income_tax_bracket_thresholds_separate, 3=income_tax_bracket_thresholds_head_of_household, 4=income_tax_bracket_thresholds_joint}
foreign_earned_income_of_individual: decimal = 0
housing_cost_amount_of_individual: decimal = 0
individual_age_at_close_of_calendar_year: decimal = 0
individual_is_child_of_taxpayer_or_descendant_of_such_child: bool = false
individual_is_permanently_and_totally_disabled: bool = false
individual_is_qualified_individual: bool = false
individual_is_sibling_stepsibling_or_descendant_of_such_relative: bool = false
individual_is_student: bool = false
individual_is_younger_than_taxpayer: bool = false
individual_may_be_claimed_as_qualifying_child_by_two_or_more_taxpayers: bool = false
individual_own_support_fraction_provided_by_individual: decimal = 0
individual_principal_place_of_abode_with_taxpayer_fraction: decimal = 0
is_spouse_of_taxpayer: bool = false
is_taxpayer: bool = false
no_parent_of_individual_is_a_claiming_taxpayer: bool = false
noncitizen_exception_to_other_dependent_credit_under_subsection_h: bool = false
parents_filing_status: integer = 0 (eq 1)
parents_of_individual_may_claim_individual_but_no_parent_claims: bool = false
person_is_child_within_federal_tax_child_definition: bool = false
qualified_individual_social_security_number_included_on_return: bool = false
qualifying_child_marital_status_requires_section_151_entitlement: bool = false
qualifying_child_name_age_and_tin_included_on_return: bool = false
qualifying_child_name_included_on_return: bool = false
qualifying_child_principal_place_of_abode_is_in_united_states: bool = false
qualifying_child_ssn_included_on_return: bool = false
qualifying_child_ssn_is_valid_for_subsection_h: bool = false
qualifying_child_tin_included_on_return: bool = false
qualifying_child_tin_issued_on_or_before_return_due_date: bool = false
return_filed_only_for_claim_of_refund: bool = false
spouse_has_no_gross_income_for_calendar_year: bool = false
spouse_is_dependent_of_another_taxpayer: bool = false
taxpayer_adjusted_gross_income_higher_than_highest_parent_adjusted_gross_income: bool = false
taxpayer_entitled_to_section_151_deduction_for_child_or_would_be_but_for_section_152_e: bool = false
taxpayer_has_highest_adjusted_gross_income_among_claiming_taxpayers: bool = false
taxpayer_household_is_child_principal_place_of_abode: bool = false
taxpayer_is_parent_of_individual: bool = false
taxpayer_or_spouse_ssn_included_on_return: bool = false
taxpayer_or_spouse_ssn_is_valid_for_subsection_h: bool = false
tin_included_on_return_claiming_exemption: bool = false
would_be_entitled_to_child_deduction_but_for_parent_release_rule: bool = false
TaxUnit (116)
active_service_compensation_as_commissioned_officer_excluding_pensions_and_retirement_pay: decimal = 0
active_service_compensation_as_enlisted_member_excluding_pensions_and_retirement_pay: decimal = 0
adjusted_gross_income: decimal = 0
alternative_minimum_tax_foreign_tax_credit: decimal = 0
amounts_paid_for_services_as_employee_of_united_states_or_agency: decimal = 0
amounts_received_for_services_performed_as_employee_of_united_states_or_agency: decimal = 0
amounts_received_for_services_performed_as_employee_of_united_states_or_agency_attributable_to_period_before_change: decimal = 0
amt_kiddie_tax_applies: bool = false *
amt_part_iii_required: bool = false *
amt_tax_including_capital_gains: decimal = 0
armed_forces_member_in_missing_status_during_vietnam_conflict_as_result_of_conflict: bool = false
armed_forces_missing_status_active_service_compensation: decimal = 0
bona_fide_resident_of_puerto_rico_years_before_change: decimal = 0
bona_fide_resident_of_specified_possession_during_entire_taxable_year: bool = false
capital_gains_28_percent_rate_gain: decimal = 0
cdcc: decimal = 0
childless_taxpayer_or_spouse_age_eligible_for_eitc: bool = false
childless_taxpayer_principal_place_of_abode_in_united_states_more_than_half_year: bool = false
civilian_employee_in_missing_status_during_vietnam_conflict_as_result_of_conflict: bool = false
civilian_employee_missing_status_active_service_compensation: decimal = 0
commissioned_officer_in_armed_forces_excluding_commissioned_warrant_officer: bool = false
credits_before_section_931_denial: decimal = 0
credits_before_section_933_denial: decimal = 0
credits_properly_allocable_or_chargeable_to_amounts_excluded_under_section_931: decimal = 0
credits_properly_allocable_or_chargeable_to_amounts_excluded_under_section_933: decimal = 0
ctc_advance_payments_received: decimal = 0
ctc_foreign_earned_income_exclusion_adjustment: decimal = 0
ctc_fraud_disallowance_period_applies: bool = false
ctc_phaseout_joint_threshold_applies: bool = false *
ctc_phaseout_separate_threshold_applies: bool = false *
ctc_possession_income_exclusion_adjustment: decimal = 0
ctc_puerto_rico_income_exclusion_adjustment: decimal = 0
ctc_reckless_or_intentional_disregard_disallowance_period_applies: bool = false
ctc_subsection_h_special_rules_apply: bool = true (overlay) *
deductions_other_than_section_151_before_section_931_denial: decimal = 0
deductions_other_than_section_151_before_section_933_denial: decimal = 0
deductions_other_than_section_151_properly_allocable_or_chargeable_to_amounts_excluded_under_section_933: decimal = 0
deductions_properly_allocable_or_chargeable_to_amounts_excluded_under_section_931: decimal = 0
eitc_disallowance_period_applies: bool = false
eitc_relevant_investment_income: decimal = 0
elderly_disabled_credit: decimal = 0
employee_compensation_includible_in_gross_income: decimal = 0
energy_efficient_home_improvement_credit: decimal = 0
exemptions: decimal = 0
filer_adjusted_earnings: decimal = 0
filing_status: integer = 0 {1=income_tax_bracket_thresholds_joint, 2=income_tax_bracket_thresholds_separate, 3=income_tax_bracket_thresholds_head_of_household, 4=income_tax_bracket_thresholds_joint}
foreign_tax_credit: decimal = 0
form_4972_lumpsum_distributions: decimal = 0
hospitalized_resulting_from_combat_zone_wounds_disease_or_injury: bool = false
income_derived_from_sources_within_puerto_rico: decimal = 0
income_derived_from_sources_within_specified_possessions: decimal = 0
income_effectively_connected_with_trade_or_business_within_specified_possessions: decimal = 0
individual_changes_residence_from_puerto_rico_during_taxable_year: bool = false
individual_is_bona_fide_resident_of_puerto_rico_during_entire_taxable_year: bool = false
individual_is_citizen_of_united_states: bool = false
legally_separated_under_decree_of_divorce_or_separate_maintenance: bool = false
lifetime_learning_credit: decimal = 0
long_term_capital_gains: decimal = 0
maximum_enlisted_amount_for_commissioned_officer_months: decimal = 0
member_below_grade_of_commissioned_officer_in_armed_forces: bool = false
misc_deduction: decimal = 0
months_beginning_after_combatant_activities_termination: decimal = 0
net_capital_gain_taken_into_account_as_investment_income_under_section_163_d_4_B_iii: decimal = 0
net_earnings_from_self_employment_after_self_employment_tax_deduction: decimal = 0
net_investment_income_tax: decimal = 0
new_clean_vehicle_credit: decimal = 0
non_refundable_american_opportunity_credit: decimal = 0
non_refundable_ctc: decimal = 0
nonresident_alien_income_not_connected_with_united_states_business: decimal = 0
officially_absent_from_post_of_duty_without_authority: bool = false
penal_institution_service_compensation: decimal = 0
pension_or_annuity_amount: decimal = 0
possession_is_american_samoa: bool = false
possession_is_guam: bool = false
possession_is_northern_mariana_islands: bool = false
prior_deficiency_denial_without_required_eligibility_information: bool = false
puerto_rico_source_income_attributable_to_puerto_rican_residence_period_before_change: decimal = 0
qualified_dividend_income: decimal = 0
qualified_retirement_penalty: decimal = 0
recapture_of_investment_credit: decimal = 0
residential_clean_energy_credit: decimal = 0
salt_deduction: decimal = 0
satisfies_eitc_separated_spouse_rules: bool = false
savers_credit: decimal = 0
served_in_combat_zone_during_month: bool = false
short_term_capital_gains: decimal = 0
spouse_dies_during_taxable_year: bool = false
spouse_includes_required_social_security_number_on_return: bool = false
spouse_not_member_of_household_final_month_count: decimal = 0
standard_deduction: decimal = 0
subsidized_state_work_activity_service_compensation: decimal = 0
tax_unit_itemizes: bool = false
taxable_income: decimal = 0
taxable_year_begins_after_exemption_amount_zero_start: bool = false *
taxable_year_begins_before_senior_deduction_termination: bool = false
taxable_year_closed_by_reason_of_taxpayer_death: bool = false
taxable_year_is_full_12_months: bool = true (overlay)
taxable_year_months: decimal = 12 (overlay)
taxpayer_claims_section_911_benefits: bool = false
taxpayer_elects_to_treat_section_112_excluded_amounts_as_earned_income: bool = false
taxpayer_files_separate_return: bool = false
taxpayer_household_cost_fraction_furnished: decimal = 0
taxpayer_identification_number_issued_after_return_due_date: bool = false
taxpayer_includes_required_social_security_number_on_return: bool = false
taxpayer_is_dependent_for_section_151_to_another_taxpayer: bool = false
taxpayer_is_individual: bool = false
taxpayer_is_nonresident_alien_for_any_portion_of_year: bool = false
taxpayer_is_qualifying_child_of_another_taxpayer: bool = false
taxpayer_maintains_household_as_home: bool = false
taxpayer_married_at_close_of_taxable_year: bool = false
taxpayer_married_at_time_of_spouse_death: bool = false
taxpayer_treated_as_resident_by_section_6013_g_or_h_election: bool = false
unrecaptured_section_1250_gain: decimal = 0
unreported_payroll_tax: decimal = 0
used_clean_vehicle_credit: decimal = 0
vietnam_combat_zone_hospitalization_month_after_january_1978: bool = false