Back Child Support in Quebec: 2026 Guide to Arrears, Collection & Enforcement

Back child support in Quebec is past-due support that a paying parent owes after missing court-ordered payments. As of January 2026, Revenu Québec administers a universal Support-Payment Collection Program that enforces arrears through automatic wage deduction, tax refund seizure, bank account seizure, driver's licence suspension, and Canadian passport suspension. Under Civil Code of Québec art. 596.1, child support arrears cannot be reduced retroactively, and unpaid amounts accrue interest at the legal rate of 5% per year. Roughly 70% of support files are enforced through deduction at source from the payer's salary.

This guide explains how arrears accumulate, what powers Revenu Québec holds to recover child support debt, how indexation adds to what you owe, and what options exist if you owe back child support or are owed past due child support in Quebec.

Key Facts: Back Child Support in Quebec (2026)

Filing fees as of February 2026. Verify current amounts with your local Superior Court clerk, as they are indexed annually each January 1.

What Is Back Child Support in Quebec?

Back child support in Quebec is the cumulative total of court-ordered support payments that a paying parent has failed to remit by their due dates. Each missed monthly payment becomes an enforceable debt the moment it is unpaid, and the balance grows with 5% annual legal interest plus any uncollected January indexation. Quebec law treats child support as a matter of public order, meaning no parent can waive it by agreement.

Unlike ordinary contractual debts, child support arrears in Quebec carry extraordinary enforcement weight. The amount owed is determined by the existing parenting order or judgment, calculated under the Québec Model for the Determination of Child Support Payments when both parents reside in the province. When a payment is missed, the recipient does not need to take separate legal action to prove the debt exists; the original judgment already establishes the obligation. Revenu Québec automatically detects non-payment and begins recovery, which distinguishes Quebec from provinces where the recipient must request enforcement. This automatic system is why past due child support in Quebec is among the most reliably collected in Canada.

How Does Revenu Québec Collect Back Child Support?

Revenu Québec collects back child support through a universal Support-Payment Collection Program that applies automatically to nearly all support judgments rendered in Quebec. When a court issues a parenting order with support, the court clerk forwards a copy to Revenu Québec, which opens a file and contacts both parents. Approximately 70% of files use deduction at source, where the employer withholds support directly from the payer's salary and remits it to Revenu Québec.

The program operates without requiring action from the recipient. If support is not received, Revenu Québec independently detects the shortfall and initiates recovery measures. The agency orders the payer's employer to subtract enough from wages to cover both the ongoing obligation and any accumulated child support debt. When salary deductions are insufficient, Revenu Québec issues a payment order, and in certain cases requires the payer to provide a financial guarantee called "security." Deductions can also be taken from other income sources belonging to the payer, including government benefits and contract payments. This layered approach means that owing back child support in Quebec rarely escapes collection, because the system reaches multiple income streams rather than relying on a single garnishment.

What Enforcement Powers Does Revenu Québec Have?

Revenu Québec holds extensive enforcement powers over back child support, including wage garnishment, tax refund interception, bank account seizure, property seizure, Canadian passport suspension, and as of January 1, 2026, driver's licence suspension. These measures escalate when a payer ignores standard wage deduction, giving Revenu Québec one of the strongest collection toolkits of any Canadian support agency.

The 2026 expansion significantly increased pressure on parents who owe child support. Effective January 1, 2026, Revenu Québec can have a delinquent payer's driver's licence suspended for non-payment. In serious cases, the agency can seize and sell a payer's movable and immovable property under judicial authority, applying the net proceeds to the support debt. Where property is seized and sold, the payer is also responsible for the reasonable costs and fees Revenu Québec incurs during the seizure and sale. To make a debt enforceable, Revenu Québec can issue a certificate attesting to the amount and payability of the arrears; once filed at the office of the Superior Court, that certificate carries all the legal effects of a court judgment. These powers apply not only to payers but to third parties such as employers who fail to remit deducted amounts.

Can Back Child Support Be Reduced or Cancelled in Quebec?

Back child support generally cannot be reduced retroactively in Quebec. Under Civil Code of Québec art. 596.1, a court cannot retroactively reduce child support arrears that have already accrued, meaning accumulated debt remains fully enforceable even if the payer's financial circumstances later change. This protects the child's right to support that was legally owed during past periods.

Quebec law draws an important distinction between two different applications. A retroactive variation asks the court to lower the amount owed for a past period because the payer's actual income, parenting arrangement, or entitlement status during that period justified a smaller payment than the order reflected. A request to rescind arrears, by contrast, acknowledges the past amount was correct but asks the court to forgive part of it due to the payer's current inability to pay. The Civil Code art. 596.1 restriction makes retroactive reduction of validly accrued child support debt very difficult to obtain. A payer who experiences a genuine drop in income should apply promptly to vary support going forward, because waiting allows arrears to accumulate at 5% interest and these cannot simply be erased later. The motion to vary existing support costs CAD $108 to file in Superior Court.

How Does Indexation Increase Back Child Support?

Indexation increases back child support in Quebec by adding an annual cost-of-living adjustment to the support amount every January 1. Support payments are indexed automatically under the Civil Code of Québec in accordance with the Pension Index set out in the Act respecting the Québec Pension Plan. When a payer fails to apply this annual increase, the unpaid difference accumulates as enforceable arrears that cannot be reduced retroactively.

This automatic adjustment catches many paying parents off guard. Even if a payer continues sending the original ordered amount, they fall into arrears each year unless they increase their payment to match the indexed figure. The shortfall between the old amount and the indexed amount becomes child support debt subject to the same 5% legal interest and the same aggressive collection measures. Indexation applies to all judgments awarding support unless the judgment specifically states otherwise, and it continues even for parents who are otherwise exempt from the Support-Payment Collection Program. Revenu Québec adjusts wage deductions automatically when indexation takes effect each January 1, so files inside the program self-correct, but parents paying privately must track the index themselves to avoid silently accumulating past due child support.

How Is Interest Calculated on Child Support Arrears?

Interest on child support arrears in Quebec accrues at the legal rate of 5% per annum on the outstanding balance. This interest compounds the cost of unpaid support over time, meaning a parent who owes child support faces a debt that grows substantially the longer it remains unpaid, in addition to the principal arrears and any uncollected indexation amounts.

The 5% legal interest rate applies to the accumulated arrears balance, not just the original missed payments. Because Quebec law prohibits retroactive reduction of arrears under Civil Code art. 596.1, this interest cannot be waived simply because the payer struggled financially. Consider a parent who falls behind on $500 monthly support for two years: the $12,000 principal accrues interest throughout that period, and Revenu Québec collects both principal and interest through wage deduction or seizure. This compounding structure is a deliberate policy choice that incentivizes prompt payment, since delay materially increases the total child support debt. Parents who anticipate falling behind should contact Revenu Québec and seek a formal variation rather than allowing interest to accumulate against a debt that cannot later be reduced.

What Happens If the Paying Parent Leaves Quebec?

Back child support remains fully enforceable even if the paying parent leaves Quebec. Revenu Québec manages cross-jurisdictional collection through reciprocal agreements with every Canadian province and territory, as well as a special enforcement arrangement with France. A judgment rendered in Quebec can be enforced against a payer living elsewhere, and Revenu Québec continues collecting and transferring payments regardless of where either parent resides.

For interprovincial cases, Revenu Québec coordinates with the maintenance enforcement program in the payer's new province to garnish wages, intercept tax refunds, and apply other recovery measures available in that jurisdiction. The recipient does not lose their entitlement when the payer relocates; the obligation follows the payer across borders. For cases involving France, the Ministère de la Justice du Québec administers collection under the bilateral agreement that makes judgments enforceable between the two jurisdictions. When parties move abroad more generally, one parent continues sending payments to Revenu Québec, which forwards the money to the other parent no matter where they live. This cross-border reach means relocating offers no escape from owing back child support in Quebec, and arrears continue to accrue 5% interest during any enforcement delay.

How Do You Collect Back Child Support You Are Owed?

To collect back child support you are owed in Quebec, you generally do not need to take action because Revenu Québec automatically detects missed payments and pursues recovery. If your support judgment was rendered in Quebec, the agency already administers your file and will issue wage deductions, payment orders, or seizure measures against the payer without a separate application from you.

For recipients, this universal program removes most of the burden of enforcement. The court clerk forwards your support judgment to Revenu Québec, which opens a file and monitors compliance. When the payer falls behind, Revenu Québec acts on your behalf using its full enforcement toolkit, including tax refund interception and the new 2026 driver's licence suspension power. If you fall into one of the narrow legal exceptions and your file is not in the program, or if your judgment was issued outside Quebec, you should contact Revenu Québec to confirm your enrolment status. You can also obtain an enforceable certificate of the debt amount, which once filed at the Superior Court office carries the force of a judgment. Keeping accurate records of payments received helps you and Revenu Québec verify the precise arrears balance, including unpaid indexation and accrued 5% interest.