The core difference in one sentence
With joint tenancy, both parties own the whole property equally and neither can sell their share independently. With tenants in common, each party owns a defined share that they can pass on, sell, or assign as they choose.
That's the essential distinction. Everything else follows from it.
Joint tenancy: what it means in practice
Joint tenants own the property together, not in separate portions. There's no "your 50%" and "my 50%" — you each own all of it, together.
The significant consequence of this is the right of survivorship: when one joint tenant dies, their interest passes automatically to the surviving joint tenant(s), regardless of what their will says. The property bypasses probate entirely.
For a married couple buying their family home, this is often exactly what they want. For a multigenerational arrangement, it's usually the wrong structure — and sometimes a serious problem.
The issue: If a parent and adult child own a property as joint tenants and the parent dies, the child inherits the entire property automatically. That sounds fine — until there are other children, or a spouse, or the parent wanted to leave their share to someone else. Joint tenancy overrides the will entirely.
Tenants in common: what it means in practice
Tenants in common each own a defined percentage of the property. Those percentages don't have to be equal — you might own 70% and your adult child 30%, or 80/20, or 60/40. The split can reflect contributions, agreements, or whatever the parties decide.
Each party can pass their share on through their will. This is the structure most multigenerational arrangements should use. It allows:
- Unequal shares that reflect different contributions
- Each party's share to pass according to their own wishes
- Party B to build equity formally and documentably, even without a mortgage
- A clear basis for calculating what each party is owed if the arrangement ends
The equity question for multigenerational arrangements
If an adult child can't get a mortgage but will be contributing monthly and building toward an ownership stake, that stake needs to be legally defined somewhere. Tenants in common is the mechanism that makes it real.
The typical approach: the property is owned initially by Party A (100%). A co-ownership agreement defines the terms under which Party B builds their share over time — based on contributions, a formula, or agreed milestones. When the share transfer is triggered, a new title is registered reflecting both parties as tenants in common in their respective shares.
Without this structure, Party B's equity is a promise, not a legal right.
What about a Declaration of Trust?
A Declaration of Trust specifies what percentage each tenant in common owns, what happens when the property is sold, and how disputes are resolved. If your shares are anything other than 50/50, or if your contributions differ in any way, you need one.
It should cover:
- Each party's current ownership percentage
- How and when shares can change as Party B makes contributions
- What happens if one party wants to sell
- How the property is valued for buyout purposes
- What happens on death, separation, or bankruptcy
This is a solicitor's job, not a template job. The cost is usually $500–$1,500 and it is one of the best investments a multigenerational arrangement can make.
Which should you choose?
For most multigenerational arrangements: tenants in common, with a Declaration of Trust.
Joint tenancy is appropriate when both parties want the right of survivorship, the shares are equal, and the arrangement is between people who would naturally inherit from each other anyway.
Tenants in common is appropriate when shares are unequal, one party is building equity over time, there are other potential beneficiaries, or you want flexibility on what happens to each party's share.
This article provides general information only and does not constitute legal advice. Property law varies by jurisdiction. Always consult a qualified solicitor or attorney before entering into any co-ownership arrangement.