Background: There is a lack of evidence in Canada surrounding the costs to parents and society to raise a child with intellectual disability. Knowledge of these costs is necessary to ensure appropriate governmental support to families and to assess the financial impact of new diagnostic tests and treatments. Method: We adapted 2 paper-based cost diaries into an online retrospective survey and evaluated it using a small pilot study of individuals with Down syndrome. Results: Parents completed the survey with apparent ease, giving answers requiring little clarification; they used comment fields to add data that elaborated on both financial and emotional costs. Costs appeared concordant with those reported in other countries. Conclusion: The survey successfully documents care time required, impact on employment, and other expenses. Minor modifications were made as a result of this pilot, and the survey is now available for wider use.