In Canada, postdated cheques should not be cashed before the date that is written on it. If it is cashed early, the cheque writer can ask their financial institution to put the money back into their account up to the day before the cheque should have been cashed . On the other hand, in the United States, once a check is signed, it becomes legal tender and can be cashed before the date written on the postdated check .
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•  Government of Canada – Financial Consumer Agency of Canada: Post-dated Cheques
• Canadian Bankers Association: Cheques – What You Need to Know
•  Quicken Loans: Do You Postdate Your Checks? Here Are Some Things to Know
• About.com: Postdated Checks
• Consumer Finance Bureau Protection (CFBP): Postdated Checks