Typically, audits occur on an annual basis. Most audits are done on an annual basis to align with the fiscal year-end. Depending on the reason for the audit, audits can be done more often, such as quarterly, or can sometimes be only a one-time occurrence.

Many choose to purchase Audit Defence for this purpose. That way they won't need to deal with the CRA but the Audit Defence will work it out for you. It must be purchased before you file your income tax return.  Maybe something to think about for next year. 

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