Retroactive Child Support in British Columbia

Retroactive child support is support ordered for a period that has already passed, rather than only from your application forward. It arises when support was never set, when the payor's income rose and support was never adjusted, or when arrears built up under an existing order. If you have questions about a past period, our family law team can review it with you from our Surrey office.

What is Retroactive Child Support?

Retroactive child support covers a period in the past when a parent paid less than the Guidelines required — or paid nothing at all. In British Columbia, section 152 of the Family Law Act allows a court, on application, to change, suspend or terminate a child support order "prospectively or retroactively".

The court must first be satisfied of one of three things: a change in circumstances under the child support guidelines, substantial evidence that was not available at the previous hearing, or evidence of a lack of financial disclosure by a party discovered after the last order was made. Section 152 applies where a child support order already exists. If support was never ordered in the first place, the application is for a first order under section 149 of the Family Law Act.

A retroactive order is a debt for a past period. How it gets paid — as a lump sum, or by instalments on top of ongoing support — is decided by the court or settled in your agreement, using current financial information from both parents. Retroactive support is one of several issues that come up when parents separate; see our family law services in BC for the wider picture.

How is Retroactive Child Support Calculated in British Columbia?

In the ordinary case, the monthly table amount is set by the Federal Child Support Guidelines using the paying parent's annual income, the number of children, and the province where that parent lives.

That income figure is the payor's gross annual income, not income after tax. Section 15 of the Guidelines directs that annual income be determined in accordance with sections 16 to 20, and section 16 provides that, "[s]ubject to sections 17 to 20", annual income is determined "using the sources of income set out under the heading 'Total income' in the T1 General form issued by the Canada Revenue Agency and is adjusted in accordance with Schedule III" — the Department of Justice identifies that as line 15000 of the return.

Those Schedule III adjustments do subtract certain employment items, including annual union and professional dues, but income tax is never deducted first: the Department of Justice explains that the Guidelines use gross income and that the federal table amounts already account for taxes.

Both parents' incomes become relevant in two situations: when section 7 special expenses are shared in proportion to income, and when the children spend at least 40% of their time with each parent.

For a retroactive claim you need the table that was in force during the period claimed. The federal child support table look-up offers a 2017 version for amounts between November 22, 2017 and September 30, 2025, and a 2025 version for October 1, 2025 onward. For a period before November 22, 2017, you need the table version that was in force at the time — Justice Canada still publishes the 2011 look-up for those earlier periods. If the correct amount was not paid for a period that has already passed, a court can order the shortfall paid — this is retroactive child support. For the full calculation, see our complete guide to child support in BC.

How Far Back can I Claim Retroactive Child Support?

As a rough guideline, a retroactive claim will usually reach back about three years. In D.B.S. v. S.R.G., 2006 SCC 37, the Supreme Court of Canada treated the date of effective notice as the general starting point for a retroactive award, and set roughly three years as the outer reach in the usual case. Effective notice does not require you to take legal action — all that is required is that the topic be broached, after which the payor can no longer assume the status quo is fair. Raising the issue early does not by itself preserve the whole period, so where years pass before formal steps are taken the dates in your own case need to be looked at closely.

Two things can push the start date further back. First, where the payor has engaged in blameworthy conduct, D.B.S. makes the date the circumstances changed materially the presumptive start date instead.

Second, in Michel v. Graydon, 2020 SCC 24, the Court held that s. 152 of BC's Family Law Act authorizes a court to retroactively vary child support whether or not the beneficiary is still a child when the application is made, and whether or not the order has already expired — so a claim about a past period is not necessarily lost because the child is now an adult or support has ended. In that case the payor had understated his income across most of the years between the 2001 consent order and the 2012 termination of his support obligation, and the hearing judge's award was restored.

Whatever period you claim, the case usually turns on financial evidence: your income and the other parent's income across those years. Where a parent's reported income does not reflect what they actually earn, section 19 of the Guidelines lets the court impute an amount it considers appropriate, including where a parent is intentionally under-employed or has diverted income. Tax returns, notices of assessment, and business records are the usual proof.

What if the Other Parent Doesn't Agree to Pay Retroactive Child Support?

The other parent's agreement is not required — a retroactive claim can be started without it. A parent whose income has risen carries an ongoing obligation to disclose that change and to adjust support accordingly, rather than waiting to be asked. Michel v. Graydon treated a payor's failure to accurately disclose his income, and to disclose material changes in it, as blameworthy conduct justifying a retroactive order.

The four D.B.S. factors

D.B.S. sets out four factors a court weighs in deciding whether a retroactive award is appropriate and how far back it should reach:

1. The reason for the delay in seeking support. An unreasonable delay counts against an award; the concurring reasons in Michel v. Graydon ask whether the reason given is understandable, taking into account the social context in which the decision to seek support was made.
2. The conduct of the payor parent. Blameworthy conduct — broadly defined as privileging the payor's own interests over the child's right to appropriate support — counts in favour of an award.
3. The circumstances of the child, including the child's needs at the time the support should have been paid.
4. Hardship that a retroactive award would cause the payor.

Because the analysis is discretionary and evidence-driven, the financial record for the years in question usually decides the outcome.

How do I Enforce a Retroactive Child Support Order?

To enforce a retroactive child support order you can either apply to the court or enrol the order with the BC Family Maintenance Agency, the Crown agency that now delivers what was formerly the Family Maintenance Enforcement Program. Which forms you file depends on whether your matter is in the BC Provincial Court or the Supreme Court of BC. In Supreme Court, a contested support claim will normally pass through the judicial case conference step in BC Supreme Court before a hearing.

Talk to a Surrey Family Lawyer About Retroactive Child Support

If support was not paid at the right level for a past period, gather the tax records for those years and get advice on how far back a claim can realistically reach in your circumstances. You can book a free consultation about retroactive child support with our child support lawyers in Surrey, or call (778) 381-9977. If your separation is at an earlier stage, our guide to getting divorced in BC sets out the steps.