Yes, you may pay in installments. As per Canada Revenue Agency (CRA):
Payments to the CRA: If you cannot pay your debt in full, the CRA can help you set up a payment arrangement. A payment arrangement is an agreement with the CRA to pay your balance in several regular payments over a period of time.
If you owe an amount to the CRA, they will work with you to find the best way to pay your debt through a payment arrangement. You have to calculate your monthly income and expenses and determine how much you can pay for each period. Then, you have to contact CRA 1-866-256-1147 (given in the website) to plan the payments.
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