Why do my Total Taxes paid change after I enter my spouse's T4?

[gavindbush]

After I enter my T4 (Employment Income of $102,000) and the appropriate deductions, a refund of approximately $2,800 shows. When I enter my wife's T4 (Employment Income of $106,000) and the appropriate deductions, my "Total Taxes" increases by about $5400 (from $21,600 to $27,100) so I am left with a balance owing.

If I enter the T4's the other way (her's first, mine second), my wife's initial refund is $6,100 (Total Taxes of $22,300) - when my T4 is added, her Total Taxes increase to $28,400 and refund drops to $13.67.

Does filing our taxes jointly increase our taxation rates and decrease our returns?

[Lyne-TurboTax · Accepted solution]

Thank you for your question.

It's normal.

If you did joint return or separately one, all your deduction will be based on the family income.

All your medical expenses, deduction for child care or another deduction will be lower if the family income increase.

Have a good day.