The rule of 65, and how two years of age changes everything
Duration is usually the more consequential half of a spousal support outcome, and one arithmetic rule decides it.
6 min read
What is the rule of 65 in spousal support?
Under the Spousal Support Advisory Guidelines, spousal support is indefinite rather than time-limited where a marriage lasted at least five years and the years of marriage plus the recipient's age at separation total 65 or more. A 12-year marriage ending when the recipient is 53 qualifies, because 12 plus 53 is 65. The same marriage ending when they are 50 does not, and would instead produce a duration of roughly 6 to 12 years.
Two conditions, both required
The rule has two limbs and both must be satisfied.
First, the relationship must have lasted at least five years. This gate is absolute — a four-year marriage does not qualify no matter how old the recipient is. A four-year relationship ending when the recipient is 70 sums to 74, well over 65, and still produces a duration of only two to four years.
Second, years of cohabitation plus the recipient's age at separation must reach 65.
The five-year gate is the part most often forgotten, because the arithmetic of the second limb is so memorable that people stop reading.
There is also a separate route to indefinite support that ignores age entirely: any marriage of 20 years or more.
The cliff edge, and why it feels arbitrary
Because both inputs are whole numbers, the rule produces a hard boundary. One year of age or one year of cohabitation can flip a case from a defined range to an open-ended obligation.
A 15-year marriage ending when the recipient is 49 sums to 64: duration of 7.5 to 15 years. The same marriage ending when they are 50 sums to 65: indefinite.
That is a large difference to hang on a single year, and it is a recognised feature of the guidelines rather than an oversight. The rationale is that a recipient who is older at separation has materially less working life left in which to become self-sufficient, and the guidelines draw the line somewhere.
It is worth knowing precisely where your own case sits relative to that boundary before negotiating.
Indefinite does not mean permanent
This is the most common misunderstanding, and it causes real distress on both sides.
"Indefinite" in the guidelines means the duration is not specified at the outset. It does not mean the obligation is fixed for life and cannot be revisited.
Indefinite support remains open to review and variation. A material change in either party's circumstances — the payor's retirement, a substantial change in either income, the recipient re-partnering — can all be grounds to return to it. Orders are frequently made with a review date built in.
The practical difference from time-limited support is who bears the burden of returning to court, not whether the obligation can ever end.
Cohabitation, not the wedding date
The years figure is the period of cohabitation, not the period from marriage to separation. Time spent living together before the wedding counts.
For couples who lived together for several years before marrying, this can be the difference. A couple who cohabited for four years and were married for nine have thirteen years for the formula, not nine — and that four-year difference can be exactly what pushes a case over the rule of 65 line, or over the twenty-year threshold.
It also affects the amount, since the percentage accumulates at 1.5 to 2% for every year of cohabitation.
Establishing the start date of cohabitation is therefore worth doing carefully rather than approximately.
Duration and amount trade against each other
The guidelines expressly contemplate restructuring: trading amount against duration to reach the same overall value in a shape that suits the parties.
A higher monthly figure over a shorter period, or a lump sum in place of a stream, can substitute for the formula's default shape. This is often how indefinite obligations are resolved in negotiation — the payor buys certainty, the recipient accepts a defined end in exchange for more now.
The guidelines treat the amount and duration ranges as a package rather than as two independent answers, and the total value of the award is what restructuring preserves.
Run the range first, then discuss shape. Doing it the other way round tends to produce arguments about the wrong thing.