The civil union contract is a notarized document by which the future spouses establish, among other things, their matrimonial regime.

The primary purpose of a matrimonial regime is to organize the economic relationships between spouses. The matrimonial regime also determines who will be the owner of the property acquired during the civil union.

If the future spouses choose the regime of "société d'acquêts", they will remain owners of the property acquired before their civil union, which are then considered "separate property". The property acquired during the civil union will belong to the spouse who purchased it. They belong to both spouses equally if it is impossible to determine ownership. In the event of a separation or the death of one spouse, the spouse who keeps the property must reimburse the other spouse for a portion of its value (reimbursement).

If the spouses do not choose any matrimonial regime before the celebration of the civil union, they are then subject to the "société d'acquêts" regime. This is the legal regime in Quebec.

The "séparation de biens" regime does not create any partnership or community between spouses. They therefore remain owners of the property acquired both before and during the civil union.

It should be noted that, regardless of the matrimonial regime chosen by the future spouses, they remain subject to the "patrimoine familial".

The civil union contract also allows for the provision of a donation, donation causa mortis, or mutual donation in favor of the other spouse, for certain property or all property.

The civil union contract may also include the following elements:

• the date on which the future spouses began to live together;
• the description of the assets of each spouse at the time of the civil union. This inventory drawn up by the spouses will be annexed to the civil union contract and will provide a balance sheet of the assets and liabilities of each spouse. It may be used to settle the matrimonial regime in the event of death or divorce. Couples who are already living together and have acquired property together may assign a value to these assets and classify them as jointly held property regardless of the chosen matrimonial regime. This balance sheet may be accompanied by a declaration stating that the spouses have mutually informed each other of their financial situation (income, etc.);
• economic clauses, for example, do the spouses intend to have a joint bank account, exclusive bank accounts for each spouse, a joint bank account solely for household expenses (residence, car, food, etc.)? Will the spouses have a joint credit card or exclusive credit cards? How do they intend to manage their budget? Should the spouses maintain a life insurance policy for the benefit of the other spouse (throughout their lifetime, until the end of the civil union, until the children leave, until the final payment of the house, etc.)?
• provisions regarding the name that the children will bear, as well as the values that the spouses intend to transmit to their children. The question of child support can also be addressed in the civil union contract, in which case it may involve children born from previous marriages or civil unions as well as children from their own union (care, education, sports or cultural activities, etc.);
• mechanisms to deal with a breakup by determining, for example, that both spouses must resort to mediation if a breakup occurs.