Many separating parents start with an informal arrangement: "I'll give you $500 a month for the kids." No written agreement, no court order, just a verbal understanding or text message exchange. This feels simpler and cheaper than going to court — but it carries significant legal risks for both parties. Informal arrangements create ambiguity about amounts, provide no enforcement mechanism, and can expose the payor to retroactive liability if the amount falls short of the guidelines.

Child Support Is the Child's Right

The starting principle is that child support is the right of the child, not the parents. Parents cannot contract away their children's right to guideline-level support. Even if both parents agree to a below-guideline amount, a court can override that agreement and order the full guideline amount if the matter comes before a judge. The informal agreement provides no protection against this.

Retroactive Child Support

The most serious risk of an informal arrangement is retroactive liability. Under the Supreme Court of Canada's decision in DBS v. SRG (2006 SCC 37), a court can order child support retroactive to the date when effective notice was given, or — in cases of blameworthy conduct — up to three years before the application was filed. The guideline amount is calculated for each year, and the difference between what was actually paid and what should have been paid becomes an arrears obligation.

No Enforcement Mechanism

Payments made under an informal arrangement cannot be registered with a provincial maintenance enforcement program (MEP). Without registration, the recipient has no access to government enforcement tools — wage garnishment, licence suspension, passport denial, federal interception — if payments stop. The only recourse is to go to court, obtain an order, and then register it. This process takes time and money, during which arrears accumulate.

For the payor, the lack of registration means there is no official record of payments made. If the recipient later claims they received less than was actually paid, the payor must prove payments through bank records, cancelled cheques, or other documentation — which may be incomplete or unavailable.

CRA Implications

For tax purposes, spousal support is only deductible by the payor and taxable to the recipient if it is paid under a written agreement or court order. Informal spousal support payments are not deductible, even if they are regular and well-documented. Child support is tax-neutral regardless of how it is paid — but without a written agreement, there is no formal record for the CRA to reference if either party is audited.

How to Formalize

Converting an informal arrangement into a legally enforceable one does not require going to court. The simplest approach is a written separation agreement signed by both parties. To be enforceable, the agreement should:

Once signed, the agreement can be filed with the court to give it the force of a court order, and registered with the provincial maintenance enforcement program for automatic enforcement.