15% of my take-home salary. But it really depends on whether your parents are depending on that amount to survive, or they're just safe-keeping for you till you reach certain milestones (wedding, house, having kids). Considering these 2 cases as the end of each spectrum, you can adjust accordingly, imho between 25% to 5%. But there are more important things to think about, if they rely on your income, what's going to happen if you lose your job? If they are safekeeping it for you, are you a keen investor who an make that amount of money work harder in your hands than in theirs?