The Act Governing Local Tax Regulations Article 5

To manage autonomous matters and ensure sufficient financial resources, the governments of special municipality and county (city) governments, excluding customs duty, commodity tax, and value-added business tax, may impose surtaxes on existing national taxes. However, the surtax rate must not exceed thirty percent of the originally prescribed tax rate.If the tax base of the surcharged national tax coincides with the tax base of a special tax or temporary tax, no additional surtax may be imposed.Except for adjustments made to align with increases or decreases in the central government's tax rates, the surtax rate may not be increased within two years after its implementation.