Expats do not pay tax on their foreign income or assets for the first 3 years of residency. After that, resident expats pay tax on their worldwide income. This doesn't mean you'll be taxed twice- Chile has official double taxation treaties with many countries around the world. When a treaty hasn't been signed it doesn't necessarily mean you'll be taxed twice. For example, no double taxation treaty exists with the UK but you can still claim tax credit for taxes paid in the UK against your Chilean income.

The local equivalent of the IRS or Inland Revenue is the Servicio de Impuestos Internos (SII). SII is highly organised and you must be very careful about what you declare and what you don't. There is more information here www.sii.cl

Tax returns must be prepared by an accountant and presented yearly in March/April.