Unfortunately, TurboTax does not support this form, so you must submit it to the CRA website. 

If the fair market value of all property you owned when you left Canada exceeds $25,000, you will also be required to fill out a T1161 form.

You can print and mail these forms with your tax return to the Canada Revenue Agency (CRA). You can find the address on their website: Where to mail your paper T1 return

To download the T1243 form, please visit the CRA website:
T1243 Deemed Disposition of Property by an Emigrant of Canada - Canada.ca

To download the T1161 form, please visit the CRA website: 
T1161 List of Properties by an Emigrant of Canada - Canada.ca 

For more information, please visit our TurboTax article:

How Leaving Canada Affects Capital Gains | 2022 TurboTax® Canada Tips (intuit.ca)

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