The declaration of de facto separation serves to inform the tax authorities and relevant organizations that a couple has been living apart for at least 90 days. It applies to married couples, civil unions, or Declaration of de facto union. The separation date, separate addresses, and family situation are key elements to prepare in order to update benefits, allowances, and tax credits.
This procedure applies when two spouses stop living together continuously, without a divorce or dissolution being necessary. The information provided is used to reflect the new family situation in tax and administrative files.
What is a de facto separation
A de facto separation occurs when two spouses stop living together without going through a divorce judgment or an official dissolution. This situation can apply to married couples, civil unions, or de facto unions. The cessation of cohabitation must generally last at least 90 days to be declared to tax authorities.
De facto separation leads to changes in the calculation of benefits, allowances, and taxes. Each spouse becomes responsible for declaring their own situation and income independently. Tax and social agencies use the date of separation to recalculate the amounts paid and credits granted.
According to Québec.ca, the de facto separation does not legally end the marriage or civil union, but it changes the spouses' administrative and tax obligations. The update must be made as soon as the 90-day period is reached.
Information to prepare for the de facto separation declaration

Several essential pieces of information must be prepared before making the declaration. The exact date of the separation, including the day, month, and year, serves as the starting point for calculating benefits and tax credits. This date corresponds to the time when the spouses stopped living together continuously.
The separate addresses of both spouses must be provided to confirm the end of cohabitation. The full names of both individuals, previous family status, the number of dependent children and their custody, as well as the income of each spouse are also required.
This information is used to readjust tax files and family benefits. Organizations use this data to determine the amounts to which each person is entitled based on their new family situation and individual income.
Organizations to notify of the de facto separation
Several organizations must be informed of the de facto separation to allow file updates. Revenu Québec and the Canada Revenue Agency use the date of separation to recalculate tax credits, tax benefits, and family allowances. Depending Canada Revenue Agency, the civil status must be updated to reflect the separation as soon as the 90-day period is reached.
Retraite Québec adjusts family benefits based on the new single family income. Service Canada can also modify certain files related to Old Age Security or the Canada Pension Plan when marital status or cohabitation changes.
Each organization uses the information provided to recalculate the amounts paid based on the new family situation. Spouses must inform each organization independently to ensure that files are updated correctly.
90-day waiting period and date of separation
The de facto separation must generally last at least 90 days before being reported to the tax authorities. This period makes it possible to distinguish a temporary separation from a permanent one. The date of separation corresponds to the day the spouses stopped living together continuously.
This date serves as the starting point for calculating benefits and tax credits. Couples must notify the agencies as soon as the 90-day period is reached. The information provided must be accurate and consistent between both partners to avoid errors in tax records.
The 90-day period is used by tax authorities to confirm that the cessation of cohabitation is permanent. If the spouses reconcile before the end of this period, the separation generally does not need to be declared; if cohabitation resumes after a declaration has already been submitted, the agencies must receive the corresponding update.
Practical points to know
The declaration of de facto separation can be made online, by phone, or by mail depending on the organization. Some organizations require a signed written declaration to confirm the separation. The declaration must be made by each spouse independently.
The information provided must be accurate and consistent between both spouses. De facto separation does not automatically lead to divorce or dissolution of a civil union. Spouses may reconcile and notify the agencies again if cohabitation resumes.
When the document must be submitted in solemn declaration or affidavit format, a notarization may be required. In this case, the content of the document must be finalized before it is signed, so that the information provided accurately reflects the actual situation described.
To better prepare this type of document, the FAQ online swearing-in explain the most frequently asked questions, and the document library helps locate related forms and certificates.
Official sources used
This article draws on several official sources to provide accurate and up-to-date information. The Canada Revenue Agency provides guidance on marital status and updating tax returns. Québec.ca explains the procedures related to de facto separation for married couples or those in a civil union, as well as the administrative obligations when a couple separates.
These references help to better understand the administrative obligations related to de facto separation. They specify the deadlines, the information to be provided, and the organizations to be notified in order to adjust benefits and tax credits.
Frequently Asked Questions
What is the date of separation to indicate on the declaration
The date of separation corresponds to the day the spouses stopped living together on a continuous basis. This date serves as the starting point for calculating benefits and tax credits. It must be exact and consistent between both spouses to avoid errors in tax files.
Which organizations must be informed of the de facto separation
The organizations to inform include Revenu Québec, the Canada Revenue Agency, Retraite Québec, and Service Canada. Each organization uses this information to adjust benefits, allowances, and tax credits according to each spouse's new family situation.
Why is the 90-day deadline important
The 90-day period makes it possible to distinguish a temporary separation from a permanent one. Tax authorities generally require that the cessation of cohabitation last at least 90 days before modifying files. This period confirms that the separation is stable and justifies the adjustment of benefits.
What information must be included in the declaration
Essential information includes the date of separation, separate addresses, full names, previous family situation, number of children, and income. This information makes it possible to readjust tax files and family benefits according to each spouse's new situation.
Is it possible to have a declaration of separation of fact sworn
Some organizations may require a solemn declaration or a affidavit to confirm the separation. You can use book an appointment online to have this type of document notarized. For more information on the process, see the FAQ online swearing-in or explore the document library.
Conclusion
The declaration of de facto separation makes it possible to inform the tax authorities and social security agencies of a cessation of cohabitation for at least 90 days. The separation date, separate addresses, and family situation are essential information to prepare in order to allow the updating of files.
Several agencies must be notified so that benefits and tax credits can be adjusted to reflect each spouse’s new family situation. Some forms may require notarization when the agency requests a solemn declaration or a affidavit. If such a form is requested, you can file a book an appointment online to have the document notarized.