What is the deadline to file a section 216 election after I've left Canada?

There is a filing deadline after the end of the tax year for making a section 216 election, and missing it can mean losing the ability to file that way for the year in question, leaving the flat withholding on gross rent as the only result for that year instead. Because the deadline is a hard cutoff rather than something CRA routinely extends, it's not a date to treat casually if you're relying on the election to bring your tax down to a reasonable level.

The practical complication is that non-resident landlords are often dealing with paperwork, currency conversion, and sometimes a Canadian agent or property manager coordinating information from a different country, all of which can eat into the available time faster than expected. Missing the window for one year doesn't affect your ability to elect in future years, but it does mean that year's income is stuck being taxed on the withheld gross amount.

Because the exact deadline and any conditions around it are best confirmed directly with current CRA guidance, and because the consequence of missing it is real, non-resident landlords should treat gathering the information needed to file well before the cutoff as a priority each year, rather than starting the process at the last minute.