Adjusted cost base
In some cases, special rules may apply that will
allow you to consider the cost of a property to be an amount other
than its actual cost. This section explains these rules.
Properties of a group are considered to be
identical if each property in the group is the same as all the others.
The most common examples of identical properties are shares of the
same class of the capital stock of a corporation or units of a mutual
You may buy and sell several identical properties at different prices
over a period of time. If you do this, you have to calculate the
average cost of each property in the group at the time of each
purchase to determine your adjusted cost base (ACB) (dispositions of
identical properties do not affect the ACB).
The average cost is calculated by dividing the total cost of identical
properties purchased (this is usually the cost of the property plus
any expenses involved in acquiring it) by the total number of
identical properties owned.
Any amount reported in box 42, "Amount resulting in cost base
adjustment," of the T3 slip represents a change in the capital balance
of the mutual fund trust identified on the slip. This amount is used
when calculating the ACB reported on Schedule 3, Capital Gains or
(Losses) in 2020 for the property in the year of disposition.