This week's Divorce Gotcha: A two-second math equation that can mean
paying support for the rest of your working life --- and most people
find out about it when it's already too late.

Here's how it usually goes. You're sitting across from your lawyer in a Zoom call, going over strategy and finances. Then your lawyer says something like:

"Given the ages and length of the marriage, support would likely be
indefinite."

Indefinite. You nod. You write it down. You don't fully process what that word
means. Then you get home, do the math, and realize what indefinite actually
means for your bank account over the next 20 years.

This is the Rule of 65.

Here's the equation. It takes five seconds. Take the age of the lower-earning spouse at the date of separation. Add the number of years you were married (or lived together). If that number is 65 or higher, spousal support has no automatic
end date. Not "a few years." Not "until they find a job." No end date.

The Rule of 65 comes from the Spousal Support Advisory Guidelines
(SSAG) --- the formula Ontario courts use to calculate support. It isn't technically a law --- it's a guideline. But judges rely on it heavily.

When someone leaves a long marriage later in life, their ability to
become financially independent may be limited. Courts recognize that
rebuilding a career in your 50s or 60s can be difficult.

So if the recipient's age plus years of marriage equals 65 or more,
courts may order indefinite support.

Take the age of the lower‑earning spouse at separation.

Add the years of marriage or cohabitation.

If the total is 65 or higher, the Rule of 65 applies (assuming the
relationship lasted at least five years).

Sarah separates at 52 after 18 years of marriage.

52 + 18 = 70

Rule of 65 applies. Support duration may be indefinite.

Mike separates at 45 after 15 years.

45 + 15 = 60

Rule of 65 does not apply. Support would normally be time‑limited.

Jennifer marries at 50 and separates at 60 after 10 years.

60 + 10 = 70

Rule of 65 applies even though the marriage lasted only 10 years.

There are two main situations where spousal support may become
indefinite.

Age + years together = 65 or more

If the marriage lasted 20 years or longer, support may be indefinite
regardless of age.

Indefinite does not mean forever. It simply means there is no automatic end date written into the support order. Support can still change if circumstances change.

Common reasons support may be varied or terminated include:

The Rule of 65 only applies if the relationship lasted at least five
years. Short marriages do not trigger indefinite support under this rule.

Yes. The SSAG applies to married and common‑law couples in Ontario. Years of cohabitation count toward the calculation.

The Rule of 65 is calculated based on the date of separation. Not the divorce date and not the court filing date. The actual separation date matters.

This article is for general informational purposes only and is not
legal advice. Family law outcomes depend on the facts of each case and
courts retain discretion when applying the Spousal Support Advisory
Guidelines.