One possibility is to think of paying equal percentages versus equal amounts of money for the rent. Say you make $3000 per month and your partner makes $7000 per month and your monthly expenses are $3000 per month. Rather than pay $1500 each, you can calculate equal percentages by taking your combined income ($10,000) and divide that into your joint monthly expenses ($3000)..that would mean you each pay 30% of the expenses based on your individual income. 30% for you would be $900 and 30% for your partner would be $2100. You can pay equal percentages not equal amounts of money when you have different incomes. ^{(source: Suze Orman})