HRDC started adding expiry dates on 900-series SIN cards on March 30, 2003. Under the new regulation, these SIN cards will be valid until the end of the person's authorized stay in Canada, to a maximum of five years. Existing 900-series SIN holders have a one-year period ending on April 3, 2004 to re-apply for a SIN card before their cards are deactivated. They will keep the same number but they will receive a new card with an expiry date. There is no charge for this amended card.