Members or beneficiaries of a pension plan are
untraceable when the plan administrator tries to contact them unsuccessfully, which is the case when they leave without giving an address or when documents sent to them are returned. In order to rectify the situation, the plan administrator must file
a request to find untraceable members or beneficiaries 
with
Retraite Québec.
Under the Supplemental Pension Plans Act, the administrator must file a request to find untraceable members or beneficiaries when they are entitled to:
- a refund
- payment of a retirement pension
- payment of another benefit
- other amounts following the withdrawal of their employer party to the plan or the plan's termination (e.g., part of surplus assets following the termination of the plan).
However, the Act does not prevent the administrator from filing a request to find untraceable members or beneficiaries under other circumstances, for example, when annual statements are returned by mail.