Retroactive Child Support in Ontario: Claiming What Is Owed.
Did the payor's income increase without you knowing? Understanding the 'D.B.S. Factors' and how to claim support for past years.
Legal Review: This guide was reviewed by Deepa Tailor, Senior Family Lawyer, to ensure compliance with the Supreme Court of Canada's ruling in D.B.S. v. S.R.G. regarding retroactive awards (2026).
Can I Claim Back-Dated Support?
Yes. Child support is the right of the child, and parents cannot avoid it by hiding income. If a payor's income increased in the past but the support payments did not increase to match, the recipient can ask the court for a 'Retroactive Award.' Generally, courts will go back 3 years from the date you gave 'Effective Notice' (asked for the money). However, if the payor engaged in 'Blameworthy Conduct' (hiding assets, lying), the court can go back much further.
The Supreme Court Test for Retroactivity
Judges must weigh these four factors before ordering back pay:
Reason for Delay
Why didn't you ask sooner? Valid reasons include fear of violence, lack of financial info, or waiting for a payor to stabilize. Bad reasons include simple negligence.
Conduct of the Payor
Did they hide their raises? Failure to disclose increased income is 'Blameworthy Conduct' and usually triggers a retroactive award.
Circumstances of the Child
Does the child need the money now? While support is for current needs, courts recognize that past shortfalls caused debts that still affect the child's standard of living.
Hardship to the Payor
Can the payor afford a lump sum? Courts won't order a payment so large that it bankrupts the payor, unless their bad conduct created the mess.
The Clock Starts When You Ask
What Counts as Notice?
A text, email, or lawyer's letter stating: 'I believe your income has increased, please provide disclosure so we can adjust support.' You do not need to file a motion immediately, but you must ask.
The 3-Year Rule
Once you give notice, the clock starts. If you wait too long after notice to file in court (more than 3 years), you may lose the claim. The general rule is you get support back to the date of notice, up to 3 years.
The Calculation Method
Gather NOAs
We subpoena the Payor's Notices of Assessment for the past 3-5 years.
The Differential
We calculate what should have been paid each year vs. what was paid. (Example: You paid $500/mo, but based on income, you should have paid $800/mo. The arrears are $300/mo).
Add Section 7
We add any unpaid share of special expenses (braces, daycare) from those years.
The Payment Schedule
Since the total is often large (e.g., $20,000), we propose a monthly repayment plan on top of ongoing support to avoid crushing the payor.
Retroactive Support FAQs
Related Resources
Ontario Case Law (D.B.S. Analysis)
Deep dive into the Supreme Court precedents that govern retroactive support claims.
Child Support Arrears (Debt)
Understanding enforcement options when support payments fall behind.
Child Support Modification Lawyers
How to formally change support amounts when circumstances change.
Deepa Tailor
Senior Family Lawyer
Deepa Tailor is the founder of Tailor Law. She specializes in forensic income analysis and securing retroactive support awards for parents who have been underpaid for years.
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