I just received more Tax slips and my taxes have already been filed. What should I do?

The onus is on you, the taxpayer, to submit a T1-Adjustment to CRA and notify them of the missed Slip and they will re-assess your tax year. The danger here is that if you don’t report the late slip and CRA catches the Slip not reported on your taxes – they readily assume that you, the taxpayer, have tried to mislead them by NOT reporting this income and may impose a penalty of 50% of the tax due by this omission. This could be huge and a major slam to your bank account. One client this happened to was fined $4500 as the T4 issued from BC did not arrive at their home in Alberta. CRA view is that they knew of the income they received in BC and therefore had an obligation to report it (or at least an estimate of what was earned).