You will have to start a new one if you want to prepare your return separate from your wife. When you start your return, select married as your marital status, but make sure that you choose to only prepare your own return. If you transfer your info from last year, you should see the option to only transfer for one spouse.
If you are married (or living common law), but are not preparing your spouse's return at the same time as yours, you will still need to enter some of their information.
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If you have filed a coupled return, and your wife's return has not been filed, then open your tax return and click on the "File" tab, you will see your wife's return that needs to be filed, and proceed from there to Netfile her return as indicated in our TurboTax FAQ link here: In the online edition of TurboTax, how do I submit my tax return to CRA using the NETFILE service?
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