If you are a Canadian resident (non-US citizen) you may be subject to US estate taxes if you own US assets at death.
If the values of your worldwide assets exceed US$5 million at your date of death, you will be required to pay US estate tax on the fair market value of your US assets. For 2011 estate tax rates start at 18% and quickly reach the highest rate of 35% for assets over $500,000.
Even if no US estate tax is due, you may still have to file a US estate return to claim treaty protection. The filing deadline for a US estate tax return is generally nine months after the date of death.
There are certain credits and tax planning options available to reduce these estate taxes. Contact your local KHGroup office for more information.