Can I get tax penalties waived if CRA made an error that caused me to owe more?

Possibly, yes. Under the Income Tax Act's taxpayer relief provisions, CRA has discretion to cancel or waive penalties and interest in specific circumstances, and a situation where CRA itself made an error or caused a delay that resulted in you owing more tax than you otherwise would have is one of the recognized categories CRA considers for this kind of relief.

It's important to understand that this relief is discretionary and assessed case by case, not something that happens automatically just because an error occurred. You generally need to actually request the relief and explain how CRA's specific error or delay led to the additional amount owing, rather than assuming CRA will recognize and correct the situation on its own once the mistake becomes apparent. Because these requests depend heavily on the specific facts, what exactly went wrong on CRA's end, and how directly it connects to the extra tax, penalties, or interest you're now facing, documenting the timeline and any correspondence with CRA related to the error is genuinely valuable if you're putting together a relief request. This isn't a guaranteed outcome, but it's a real avenue worth pursuing when CRA's own conduct contributed to the problem.