PolicyEngine Australia

PolicyEngine Australia is a free, open-source microsimulation model of Australia's tax and benefit system. It enables users to calculate taxes and benefits for individual households and analyze the distributional impacts of policy reforms.

Features

Comprehensive Tax Modeling

• Personal income tax with progressive brackets
• Medicare levy and surcharge
• HECS-HELP student loan repayments
• Superannuation contributions and tax treatment
• Capital gains tax (coming soon)
• GST modeling (coming soon)

Social Security Benefits

• Age Pension with means testing
• JobSeeker Payment
• Disability Support Pension
• Family Tax Benefit (Parts A & B)
• Child Care Subsidy
• Youth Allowance (coming soon)
• Parenting Payment (coming soon)

Key Capabilities

• Up-to-date parameters: Latest tax rates and benefit amounts
• Government sources: All parameters referenced to official sources
• Test-driven development: Comprehensive test coverage
• Reform analysis: Model policy changes and impacts
• Open source: Transparent and auditable

Installation

Requirements

• Python 3.10 or higher (3.13 recommended)
• pip or uv package manager

Install from source

# Clone the repository
git clone https://github.com/PolicyEngine/policyengine-au.git
cd policyengine-au

# Install with uv (recommended)
uv pip install --system -e .

# Or with pip
pip install -e .

Install from PyPI (coming soon)

pip install policyengine-au

Quick Start

from policyengine_au import AustralianTaxBenefitSystem
from policyengine_core.simulations import Simulation

# Create the tax-benefit system
system = AustralianTaxBenefitSystem()

# Define a household
situation = {
    "people": {
        "person1": {
            "age": {"2024": 35},
            "employment_income": {"2024": 80000}
        }
    },
    "households": {
        "household": {
            "members": ["person1"]
        }
    }
}

# Run simulation
simulation = Simulation(
    tax_benefit_system=system,
    situation=situation
)

# Calculate values
income_tax = simulation.calculate("income_tax", "2024")
medicare_levy = simulation.calculate("medicare_levy", "2024")

print(f"Income tax: ${income_tax[0]:,.2f}")
print(f"Medicare levy: ${medicare_levy[0]:,.2f}")

Documentation

Full documentation is available at: https://policyengine.github.io/policyengine-au

• Tax Programs - Detailed tax calculations
• Benefit Programs - Social security programs
• Developer Guide - Contributing guide
• API Reference - Technical documentation

Development

Setting up development environment

# Install development dependencies
uv pip install --system -e .[dev]

# Run tests
uv run pytest

# Format code
make format

# Build documentation
myst build docs

Running tests

# Run all tests with coverage
uv run pytest --cov=policyengine_au

# Run specific test file
uv run pytest policyengine_au/tests/policy/baseline/test_income_tax.yaml

# Run only unit tests
uv run pytest policyengine_au/tests -k "not yaml"

Contributing

We welcome contributions! Please see our Developer Guide for:

• Setting up your development environment
• Adding new parameters and variables
• Writing tests
• Submitting pull requests

Key principles

1. Test-driven development: Write tests first
2. Government sources: Reference all parameters
3. Code quality: Format with Black (79 chars)
4. Documentation: Update docs with changes

Data and Validation

PolicyEngine Australia is validated against:

• Australian Taxation Office calculators
• Services Australia payment calculators
• Published government rate tables
• Academic microsimulation models (STINMOD+, MITTS)

License

PolicyEngine Australia is licensed under the GNU Affero General Public License v3.0.

Citation

If you use PolicyEngine Australia in your research, please cite:

@software{policyengine_australia,
  title = {PolicyEngine Australia},
  author = {PolicyEngine},
  year = {2024},
  url = {https://github.com/PolicyEngine/policyengine-au}
}

Support

• Issues: GitHub Issues
• Discussions: GitHub Discussions
• Email: [email protected]
• Website: policyengine.org

Acknowledgments

PolicyEngine Australia builds on:

• OpenFisca framework via PolicyEngine Core
• Australian government data and documentation
• Open source tax-benefit modeling community

Roadmap

Near-term (Q1 2025)

• Complete Youth Allowance implementation
• Add Parenting Payment
• Implement Rent Assistance
• Add state payroll taxes

Medium-term (Q2-Q3 2025)

• GST modeling with consumption data
• Capital gains tax
• State stamp duties
• Integration with PolicyEngine web app

Long-term

• Full state and territory tax systems
• Local government rates
• Behavioral responses
• Dynamic scoring capabilities

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Note: This model is under active development. Parameters are updated regularly to reflect policy changes. Always verify calculations against official sources for critical applications.