The Cook Islands is a self-governing territory in free association with New Zealand, and its tax system is largely based on New Zealand's tax laws.

For individuals, income tax is progressive and ranges from 10% to 33%, depending on income levels. There are no social security contributions or capital gains taxes in the Cook Islands. The tax year runs from April 1st to March 31st of the following year, and tax returns are typically due by July 31st of the following year.

For corporations, the income tax rate is 20%, and there is no capital gains tax or withholding tax on dividends. However, there are a number of other taxes that may apply to businesses operating in the Cook Islands, such as a value-added tax (VAT) at a rate of 15%, payroll taxes, and stamp duties.

The Cook Islands has a simple tax system with relatively low tax rates, which is attractive for both individuals and businesses. The tax authority in the Cook Islands is the Revenue Management Division of the Ministry of Finance and Economic Management. Payment of taxes can be made at designated payment centers or through online channels.

Overall, the Cook Islands has a favorable tax environment, with a relatively simple tax system and low tax rates. Taxpayers are encouraged to seek advice from local tax advisors or government authorities for further information on tax obligations and requirements.