Can one spouse sever a joint tenancy on the family home without telling the other during a separation?

As a general property law matter, a joint tenant can often sever a joint tenancy unilaterally, without the other owner's knowledge or agreement, converting the ownership into a tenancy in common with defined shares instead of a right of survivorship. This is usually done through a specific legal step, such as transferring the interest to oneself or into a new arrangement that has the effect of ending the joint tenancy.

Where the property is a matrimonial home and the couple is still legally married, this becomes more complicated. The Family Law Act's protections around a matrimonial home focus on preventing a spouse from disposing of or encumbering an interest in it without the other's consent, and how that interacts with a unilateral severance during separation is a genuinely fact-specific and sometimes contested question, rather than something with one clean, universal answer. Courts have had to grapple with where an ordinary property law right ends and matrimonial home protections begin. Because getting this wrong can affect what each spouse ultimately receives from the property, and because timing during separation matters, anyone considering severing a joint tenancy on a shared home should get legal advice before acting, rather than assuming a unilateral severance is straightforward.