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For the 2020 tax year, prior to filing your tax return electronically with NETFILE, you will be asked to enter an Access code after your name, date of birth, and social insurance number. Your eight-character Access code is made up of numbers and letters and is located on the right side of your Notice of Assessment for a previous tax year. While this Access code is not mandatory, if you do not enter your Access code, you will not be able to use any information from your 2020 tax return when confirming your identity with the Canada Revenue Agency. You will have to rely on other information for authentication purposes. This code does not apply to you if you are filing your tax return for the first time.