ngtaxkit 0.1.1

Nigerian tax compliance SDK — VAT, PAYE, WHT, Pension, Payroll, Invoicing. NTA 2025 compliant.

ngtaxkit

Nigerian tax compliance SDK for Python. Implements the Nigeria Tax Act (NTA) 2025 — VAT, PAYE, WHT, Pension, Statutory deductions, Marketplace transactions, and Payroll batch processing.

Zero dependencies. Pure functions. Deterministic output. Python 3.10+.

Install

pip install ngtaxkit

Optional extras:

pip install ngtaxkit[pdf]    # PDF generation (fpdf2)
pip install ngtaxkit[django] # Django fields + template tags
pip install ngtaxkit[flask]  # Flask blueprint + Jinja filters
pip install ngtaxkit[fastapi]  # FastAPI router + Pydantic models

Quick Start

from ngtaxkit import vat, paye, wht, pension, payroll

# ─── VAT ────────────────────────────────────────────────────────────────────

# Calculate VAT on an amount
result = vat.calculate(amount=100_000)
# → {'net': 100000, 'vat': 7500, 'gross': 107500, 'rate': 0.075, 'rate_type': 'standard', ...}

# Extract VAT from an inclusive amount
result = vat.extract(amount=107_500)
# → {'net': 100000, 'vat': 7500, 'gross': 107500, ...}

# Zero-rated categories
result = vat.calculate(amount=50_000, category='basic-food')
# → {'vat': 0, 'rate': 0, 'rate_type': 'zero-rated', 'input_vat_recoverable': True, ...}

# Exempt categories
result = vat.calculate(amount=200_000, category='residential-rent')
# → {'vat': 0, 'rate_type': 'exempt', 'input_vat_recoverable': False, ...}

# ─── PAYE ───────────────────────────────────────────────────────────────────

result = paye.calculate(
    gross_annual=5_000_000,
    pension_contributing=True,
    nhf_contributing=True,
    rent_paid_annual=600_000,
)
# → {
#     'annual_paye': ...,
#     'monthly_paye': ...,
#     'effective_rate': ...,
#     'tax_bands': [...],
#     'reliefs': {'consolidated_relief', 'pension_relief', 'nhf_relief', 'rent_relief', 'total'},
#     'net_monthly': ...,
#     'monthly_deductions': {'paye', 'pension', 'nhf', 'total'},
#     'employer_costs': {'pension', 'nsitf', 'itf', 'total'},
#     'legal_basis': '...',
#   }

# ─── WHT ────────────────────────────────────────────────────────────────────

result = wht.calculate(
    amount=500_000,
    payee_type='company',
    service_type='professional',
)
# → {
#     'wht_amount': 50000,
#     'rate': 0.1,
#     'net_payment': 450000,
#     'credit_note_required': True,
#     'remittance_deadline': '2026-05-21',
#   }

# ─── Pension ────────────────────────────────────────────────────────────────

result = pension.calculate(
    basic_salary=300_000,
    housing_allowance=100_000,
    transport_allowance=50_000,
)
# → {
#     'pensionable_earnings': 450000,
#     'employee_contribution': 36000,
#     'employer_contribution': 45000,
#     'total_contribution': 81000,
#   }

# ─── Payroll (batch) ────────────────────────────────────────────────────────

result = payroll.calculate_batch([
    {'name': 'Amina', 'gross_annual': 4_000_000, 'state_of_residence': 'LA', 'pension_contributing': True},
    {'name': 'Chidi', 'gross_annual': 8_000_000, 'state_of_residence': 'FC', 'pension_contributing': True},
    {'name': 'Bola',  'gross_annual': 2_400_000, 'state_of_residence': 'LA', 'nhf_contributing': True},
])
# → {
#     'employees': [...],
#     'by_state': {
#       'LA': {'state_name': 'Lagos', 'irs_name': 'LIRS', 'employee_count': 2, ...},
#       'FC': {'state_name': 'FCT', 'irs_name': 'FCT-IRS', 'employee_count': 1, ...},
#     },
#     'totals': {'total_gross', 'total_paye', 'total_pension', 'total_nhf', 'employee_count'},
#   }

Trust & Explainability

Every bundled rate can be explained with source metadata, and VAT/PAYE/WHT can return a calculation trace for audit logs, user-facing receipts, and integrations.

from ngtaxkit import rates, vat, paye, wht

trace = vat.explain_calculate(amount=100_000, category="standard")
trace["result"]["vat"]       # 7500
trace["formula"]             # reproducible calculation steps
trace["rate_keys"]           # ["vat.standard.rate"]
trace["sources"][0]          # source URL, legal basis, review date, confidence
trace["warnings"]            # non-empty if a source is needs_review/disputed

rates.explain("paye.exemptionThreshold")
rates.audit()

paye.explain_calculate(gross_annual=5_000_000, pension_contributing=True)
wht.explain_calculate(amount=500_000, payee_type="company", service_type="professional")

Source metadata is bundled offline. Treat it as developer evidence, not legal advice; re-check high-impact filings against official notices and professional advice.

For deterministic tool integrations, use the tools namespace:

from ngtaxkit import tools

tools.get_tool_schemas()     # JSON Schema-compatible tool definitions
tools.get_openapi_spec()     # OpenAPI 3.1 wrapper shape
tools.call_tool(
    "ngtaxkit.vat.explain_calculate",
    {"amount": 100_000, "category": "standard"},
)

Modules

Module	Description
vat	VAT calculation, extraction, category classification
paye	PAYE income tax with NTA 2025 graduated brackets and reliefs
wht	Withholding tax by service type and payee type
pension	Contributory Pension Scheme — employee/employer splits
statutory	NHF, NSITF, ITF statutory deductions
marketplace	End-to-end marketplace transaction: VAT + commission + WHT + payout
payroll	Batch payroll with per-state aggregation and filing info
rates	Versioned rate registry — all rates, brackets, and thresholds
tools	JSON schemas, OpenAPI wrapper spec, and deterministic dispatcher

Statutory Deductions

from ngtaxkit import statutory

# Individual deductions
nhf = statutory.nhf(basic_salary=300_000)
nsitf = statutory.nsitf(monthly_payroll=5_000_000)
itf = statutory.itf(annual_payroll=60_000_000, employee_count=25)

# All at once
all_deductions = statutory.calculate_all(
    basic_salary=300_000,
    monthly_payroll=5_000_000,
    annual_payroll=60_000_000,
    employee_count=25,
)

Marketplace Transactions

from ngtaxkit import marketplace

result = marketplace.calculate_transaction(
    sale_amount=100_000,
    platform_commission=0.10,       # 10% commission
    seller_vat_registered=True,
    buyer_type='individual',
    service_category='standard',
)
# → {
#     'sale_amount': 100000,
#     'vat': {'net': 100000, 'vat': 7500, ...},
#     'total_from_buyer': 107500,
#     'platform_commission': {'rate': 0.1, 'amount': 10000, ...},
#     'seller_payout': ...,
#     'wht': {...} or None,
#     'vat_liability': {'collected_by': 'seller', 'amount': 7500, ...},
#   }

VAT Categories

Category	Rate	Type	Input VAT Recoverable
standard	7.5%	Standard	Yes
basic-food	0%	Zero-rated	Yes
medicine	0%	Zero-rated	Yes
medical-equipment	0%	Zero-rated	Yes
medical-services	0%	Zero-rated	Yes
educational-books	0%	Zero-rated	Yes
tuition	0%	Zero-rated	Yes
electricity	0%	Zero-rated	Yes
export-services	0%	Zero-rated	Yes
humanitarian-goods	0%	Zero-rated	Yes
residential-rent	0%	Exempt	No
public-transport	0%	Exempt	No
financial-services	0%	Exempt	No
insurance	0%	Exempt	No

Key Design Decisions

• Banker's rounding — all monetary values use round-half-even to 2 decimal places (Python's ROUND_HALF_EVEN)
• Legal citations — every result includes a legal_basis string citing the NTA 2025 section
• Source-backed explanations — VAT, PAYE, and WHT expose formula steps, source metadata, and warnings for values that need review
• Versioned rates — bundled as JSON; override at runtime via rates.set_custom()
• Cross-language parity — produces identical results to the TypeScript version, enforced by shared test fixtures
• Type hints — full py.typed support with strict mypy compliance

Framework Integrations

Django

# settings.py
INSTALLED_APPS = [..., 'ngtaxkit.contrib.django']

# models.py
from ngtaxkit.contrib.django import TINField, NairaField, VATCategoryField

class Invoice(models.Model):
    seller_tin = TINField()
    amount = NairaField()
    category = VATCategoryField()

# templates
{% load ngtaxkit_tags %}
{{ amount|naira }}        {# NGN 1,234,567.89 #}
{{ amount|vat_amount }}   {# NGN 92,592.59 #}
{% vat_rate "standard" %} {# 7.5% #}

Flask

from ngtaxkit.contrib.flask import init_app

app = Flask(__name__)
init_app(app)  # Registers /tax/vat/calculate, /tax/paye/calculate, /tax/wht/calculate + Jinja filters

# In templates
{{ amount|naira }}
{{ amount|vat }}

FastAPI

from ngtaxkit.contrib.fastapi import create_router

app = FastAPI()
app.include_router(create_router(), prefix="/api")
# Adds /api/tax/vat/calculate, /api/tax/paye/calculate, etc. with Pydantic validation

Install extras:

pip install ngtaxkit[django]   # Django fields + template tags
pip install ngtaxkit[flask]    # Flask blueprint + Jinja filters
pip install ngtaxkit[fastapi]  # FastAPI router + Pydantic models

License

MIT — see LICENSE

Author

Abraham Tanta

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Links

• GitHub Repository
• Changelog
• TypeScript version