To avoid double taxation, US citizens and permanent residents residing in Canada benefit from good tax planning.
The Rev. Proc. 2020-17 filed in 2020 provides tax relief for certain foreign trusts, such as RESPs, that would qualify.
US citizens and residents who own more than 10% of the shares of a foreign company or their officers are required to file a Form 5471.
If, as a US citizen or resident, you own mutual funds, you fall within the definition of passive foreign investment company.