Ontario family court forms · 2026

    Form 35.1 — the parenting affidavit, explained for fathers.

    Form 35.1 is the affidavit you file whenever you make a parenting claim — decision-making responsibility, parenting time, or contact. It is your sworn account of the children's lives and the arrangement you are asking for. Here is how to write one that helps you.

    Any parenting claim needs it

    Make a claim for decision-making, parenting time, or contact and Form 35.1 has to be filed in support of it.

    Best interests, always

    Every parenting decision turns on the child's best interests. The affidavit should speak to that test, not to blame.

    Sworn evidence

    It is an affidavit, so it is evidence under oath. Facts you can stand behind carry weight; venting does not.

    Form 35.1 is the Affidavit in support of a claim for decision-making responsibility, parenting time, or contact. It has to be filed by anyone making a parenting claim, and it is where you set out, under oath, the facts about the children — who they are, how they have been cared for, and the arrangement you say is in their best interests.

    Everything in Ontario parenting law runs through one test: the best interests of the child. Form 35.1 is your chance to speak to that test directly and factually. It is not the place for grievances about the other parent; it is the place to show the court the children's actual world and where you fit in it.

    This is a guide to what the affidavit asks for, not advice about your case. A parenting affidavit is sworn evidence, so how it is written — factual and child-focused, or angry and self-focused — genuinely affects how it lands.

    What Form 35.1 asks for

    The affidavit covers the children and their circumstances: who they are and their ages, where and with whom they live, the history of their care, their schooling, health, and any special needs, and the current parenting arrangement. It then sets out the arrangement you are asking the court to order and why that arrangement is in the children's best interests.

    The through-line the court is looking for is the children's actual experience and stability — who has been doing the day-to-day parenting, what the routine looks like, and how your proposal keeps the children's lives steady. Concrete detail about ordinary life carries more weight than adjectives.

    The parts fathers get wrong

    The biggest mistake is turning the affidavit into a case against the mother. A document that is mostly complaints reads as conflict-driven and can hurt the very claim it is meant to support. The stronger affidavit spends its words on the children — your involvement, the routine, the plan — and mentions the other parent's conduct only where it genuinely bears on the children's best interests.

    The second is being vague about the arrangement. Asking for reasonable parenting time is weaker than setting out a specific, workable schedule — school-year weeks, holidays, and how exchanges work. A father who can show a concrete, child-centred plan looks like someone ready to parent, not someone hoping the court fills in the blanks.

    The third is forgetting that it is sworn evidence. Overstatement and half-truths can be exposed and can cost you credibility across the whole case, so keep to what you can actually stand behind.

    Filing it and where the 40% line fits

    Form 35.1 attaches to and is served with the application or answer that makes the parenting claim. Because it is an affidavit, it is sworn or affirmed, and the facts in it should be ones you have first-hand knowledge of or can properly attribute.

    Parenting time also has a direct line to child support: once each parent has the children at least 40 percent of the time, the case crosses into shared parenting and support is calculated differently. The schedule you set out in Form 35.1 is where that count begins, which is one more reason to be specific about time rather than vague.

    Before you write Form 35.1

    • The key facts about each child — age, school, health, routine
    • An honest account of who has done the day-to-day parenting
    • A specific proposed schedule — school-year weeks, holidays, exchanges
    • Why your proposal keeps the children's lives stable
    • A read-through to strip out anything that is grievance rather than fact

    How Ontario parenting law works for fathers, and where the 40% line matters.

    • The best-interests factors a court actually weighs
    • Why there is no default schedule and no maternal preference
    • What the 40% line does to child support
    • How to build a parenting plan that holds up
    Read the parenting-time guide

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    Reviewed July 1, 2026 · Plain-language information for Ontario, not legal advice · Official Form 35.1 (PDF)

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