Income gaps in couples: how to split expenses fairly

Income gaps in couples: how to split expenses fairly

When one partner earns more, a strict 50/50 split can feel unfair. The lower earner might feel stretched, and the higher earner might feel overburdened by frequent exceptions. A proportional split fixes both problems.

What “fair” really means

Fair is not always equal. Fair means both partners contribute a similar percentage of their income to shared expenses.

The proportional method (simple version)

1. Add both monthly incomes.
2. Calculate each person’s share as a percentage of the total.
3. Apply those percentages to the shared expenses.

Example

• Partner A earns $3,000
• Partner B earns $2,000
• Total income = $5,000
• Partner A share = 60%
• Partner B share = 40%

If shared expenses are $2,000:

• Partner A pays $1,200
• Partner B pays $800

When proportional splits make sense

• There’s a meaningful income gap (20–30% or more)
• One partner is between jobs, studying, or changing careers
• You want to avoid constant “exceptions” to 50/50

Keep it transparent

The split should be visible to both of you and reviewed periodically. If income changes, update the percentages. This keeps the agreement fair and avoids awkward recalculations.

A quick rule of thumb

If one partner regularly feels stressed paying their share, it’s time to revisit the split. A fair system should feel sustainable for both.

Want an even faster way to calculate the split? Use a calculator once, then build the rule into your shared routine so you don’t have to renegotiate every month.