The CRA started a new AutoFill Return (AFR) service. Basically, the data the CRA has is downloaded into tax software. If one hires a tax preparer, make sure they have level 2 of the online access as it is required ( T1013 form).
Is it faster? yes. However, there is no guarantee as to the quality of the information. For example, when I first used AFR for a client’s file I downloaded all the CRA information. All the data that had income (i.e. T4s, T5s) was downloaded. Good! However, a few deductions were missing. I guess the CRA missed those or had not received them yet. Those deductions were worth thousands of dollars in tax ! Obviously, one has to be careful.
If there are joint accounts between spouses, one should get the T5. Which spouse would have the best tax position to use the T5? That requires judgement, not downloads.
If there is T3 (Trust, inheritance from a will, etc) information, that may have a different format for the CRA vs. what an individual gets in the mail. The CRA may have three T3 slips and the individual gets one (summary) T3 in the mail. The numbers and classifications of income should match in total, but this can be confusing.
I could go on. Bottom line is each person is responsible for their taxes. Do the numbers make sense? Did you use AFR properly or double-download something? Sometimes looking at paper copies helps one self-audit the information; did my employer include all of my income? Mistakes may be easier to find.
The CRA will not necessarily find the best tax position for you. That is up to you and / or your tax preparer.