Investors who wish set up a prescribed-rate loan to split investment income with a spouse, common-law partner or even their kids need to act quickly as the prescribed interest rate is set to double to two per cent on April 1, 2018 as a result of Tuesday’s Treasury Bill auction yield.

The prescribed rates are set by the Canada Revenue Agency (CRA) quarterly and are tied directly to the yield on Government of Canada 90-day Treasury Bills, albeit with a lag. The calculation is based on a formula in the Income Tax Regulations, which takes the simple average of three-month Treasury Bills for the first month of the preceding quarter rounded up to the next highest whole percentage point (if not already a whole number).

To calculate the rate for the upcoming quarter (April through June 2018), we look at the first month of the current quarter (January) and take the average of January’s T-Bill yields, which were 1.17 per cent (Jan. 9, 2018) and 1.20 per cent (Jan. 23, 2018). That average is 1.185 per cent but when rounded up to the nearest whole percentage point, we get 2 per cent for the new prescribed rate for the second quarter of 2018.

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