Getting married again comes with a different set of priorities. You have likely already built up assets, maybe a home, investments, or a business. And if you have children from your first marriage, protecting what you want to leave them becomes a real concern.
A prenuptial agreement (called a marriage contract in Ontario) is one of the most practical tools for people entering a second marriage. It lets you define what stays separate, what gets shared, and how your kids are protected if things don't work out or if you pass away.
This guide covers why prenups matter more in second marriages, what you can and can't include, how to protect your children's inheritance, and province-specific considerations across Canada.
Why prenups are more common (and more important) in second marriages
First marriages often involve two people starting from scratch. Second marriages are different. You are usually bringing:
- Assets you built before and during your first marriage
- Debts or financial obligations (like spousal support to an ex)
- Children who depend on you
- An inheritance you want to pass to your kids, not a new spouse
Without a marriage contract, provincial family law defaults apply. Depending on where you live, your new spouse could end up with a significant portion of assets you intended for your children.
A prenup lets you override those defaults and create rules that reflect your actual situation.
What a prenup can protect in a second marriage
A well-drafted marriage contract can address:
Property you are bringing into the marriage
You can define specific assets as "excluded" or "separate" property. This includes your home, investments, business interests, and savings.
Inheritance for your children
You can specify that certain assets are reserved for your children from a previous relationship, regardless of what happens in the marriage.
Future inheritance you expect to receive
If you expect an inheritance from your own parents, you can clarify that it stays with your side of the family.
Spousal support expectations
You can set out whether spousal support will be payable, and under what circumstances. This is especially relevant if one spouse is already paying support to an ex.
Debt protection
If your new spouse is bringing significant debt into the marriage, you can protect yourself from being responsible for it.
What a prenup cannot do
There are limits. Across Canada, a prenup cannot:
- Determine child custody or parenting time (courts decide this based on the child's best interests at the time)
- Waive child support obligations
- Include terms that are illegal or against public policy
In Ontario specifically, you cannot fully contract out of a spouse's right to possession of the matrimonial home. Your spouse may have the right to live there temporarily even if you owned it before the marriage and your name is the only one on title.
Protecting your children's inheritance: practical strategies
This is usually the biggest concern for people in second marriages. Here is how a prenup fits into the bigger picture.
1. Define what stays separate in the prenup
Your marriage contract can specify that certain assets (your home, your RRSP, your business) are not subject to division and are intended for your children.
2. Coordinate with your will and estate plan
A prenup handles what happens if you divorce. Your will handles what happens if you die. These need to work together.
Common estate planning tools for blended families include:
- Spousal trusts: your spouse can use assets during their lifetime, but the remainder goes to your children
- Life insurance policies naming your children as beneficiaries
- Holding property as tenants in common rather than joint tenants, so your share goes to your estate, not automatically to your spouse
3. Keep assets separate during the marriage
Even with a prenup, commingling assets can create problems. If you deposit an inheritance into a joint account or use it to pay down the mortgage on a shared home, it can become harder to trace and protect.
4. Update beneficiary designations
RRSPs, TFSAs, pensions, and life insurance policies pass outside your will based on who you named as beneficiary. Make sure these align with your intentions.
Province-specific considerations
Family law is provincial in Canada, so the rules vary by province.
Ontario
Marriage contracts are governed by the Family Law Act. The matrimonial home has special rules that limit what you can contract out of. A spouse cannot be excluded from possessory rights to the home, even if you owned it before marriage. Equalization of net family property is the default regime.
For more details, see our complete Ontario prenup guide.
British Columbia
The Family Law Act distinguishes between "family property" (generally shared) and "excluded property" (generally kept separate). Property you brought into the relationship is usually excluded, but any increase in value during the relationship may be divided. Prenups can modify these defaults.
For more details, see our complete BC prenup guide.
Alberta
The Family Property Act applies. Property brought into the marriage is generally exempt from division, but there is judicial discretion. A well-drafted agreement can provide more certainty.
Quebec
Quebec operates under a civil law system. The "family patrimony" rules require equal division of certain assets (family residences, furniture, vehicles, pension plans) regardless of who owns them. You cannot fully opt out of family patrimony rules, but you can address other property in a marriage contract.
If you are comparing advice online, make sure it applies to your province.
What makes a prenup enforceable
Courts can set aside a marriage contract if it was not done properly. To maximize enforceability:
Full financial disclosure
Both parties need to disclose their assets, debts, income, and liabilities. Hiding assets is one of the most common reasons agreements get thrown out.
Independent Legal Advice (ILA)
Each spouse should have their own lawyer review the agreement and confirm they understand it. This is not legally required everywhere, but it significantly strengthens enforceability.
No pressure or duress
Do not spring the agreement on your partner the week before the wedding. Courts look unfavourably on agreements signed under time pressure.
Fair and reasonable terms
An agreement that leaves one spouse destitute while the other keeps everything is more likely to be challenged. Fairness matters.
Proper execution
The agreement should be in writing, signed by both parties, and witnessed.
Common scenarios in second marriages
Scenario 1: You own a home and want to protect it for your kids
You can include provisions stating that the home (or a defined amount of equity) is your separate property and intended for your children. Keep in mind that in Ontario, your new spouse may still have possessory rights to the home if you live there together.
Scenario 2: You are expecting an inheritance
Your agreement can specify that any inheritance you receive remains your separate property and is not subject to division.
Scenario 3: Your new spouse has significant debt
You can include provisions clarifying that each spouse is responsible for their own premarital debts and that you will not be liable for debts incurred in the other's name.
Scenario 4: You both have children from previous relationships
You can agree that each spouse's assets will go to their own children, and set out how shared expenses (like housing costs) will be handled during the marriage.
How to bring up a prenup with your partner
This can feel awkward, but in second marriages it is often easier. Both of you have been through this before. You know that relationships can end, and you both likely have people depending on you.
Frame it as protecting both of you. A prenup is not about expecting failure. It is about being clear and avoiding a messy fight later, especially one that could hurt your kids.
For more tips, see our guide on how to talk about a prenup without starting a fight.
FAQ
Is a prenup more important for a second marriage?
Often, yes. You are more likely to have accumulated assets, have children from a previous relationship, and want clarity about what happens to your estate. The stakes are usually higher than in a first marriage.
Can I protect my children's inheritance with a prenup?
Partly. A prenup can define what assets stay separate and are intended for your children. But you also need a coordinated estate plan (will, trusts, beneficiary designations) to fully protect their inheritance.
Can my new spouse still claim against my estate if I die?
Potentially. In Ontario, a surviving spouse can elect to receive an equalization payment instead of what is left to them in the will. A marriage contract can limit or waive this right, but it needs to be drafted carefully. Other provinces have similar (but different) rules.
What if my partner refuses to sign a prenup?
That is a conversation to have before the wedding. If protecting your children's inheritance is important to you, this is a reasonable boundary. A partner who refuses to acknowledge your existing obligations may be signalling something about how they view the relationship.
How much does a prenup cost?
Costs vary by province and complexity. For a detailed breakdown, see our guide on how much a prenup costs in Canada.
Next steps
If you are entering a second marriage and want to protect your assets and your children:
- Start the prenup conversation early
- Get clear on what you want to protect
- Work with a lawyer who understands family law in your province
- Coordinate your prenup with your will and estate plan
- Keep good records and avoid commingling assets
For a complete preparation guide, check out our Canadian prenup checklist.
This article provides general information about prenuptial agreements and second marriages in Canada. It is not legal advice. Prenuply AI Inc. is not a law firm and does not provide legal services. For advice about your specific situation, consult a qualified family lawyer in your province.