How Much Should My Adult Child Pay to Live at Home?
A fair monthly number, built from your real costs — not a guess.
What This Actually Costs You Each Month
Start with what actually changes on your bills. These five categories move when someone else is living in the house — adjust any of them to match your household.
Why They’re Home Changes What’s Fair
The same dollar amount can be generous or too light, depending on why they’re home. Pick the situation that matches yours — the fair range shifts with it.
The Family Scale
This is the number that matters: where the contribution actually lands. The scale tips green when it sits inside the range for your situation, and amber when it’s noticeably outside it.
How This Compares to Renting
A contribution only means something next to the alternative. Enter what a studio or room actually rents for near you, and see how much of that your child is covering — and how much they’re saving by not paying it.
What This Means Over Time
A monthly number adds up differently depending on how long the arrangement lasts. This assumes the contribution is set aside and grows modestly instead of just being spent — a rough sense of scale, not a promise.
Three Ways to Set the Number
If you’d rather start from a plain number than a slider, here are three versions of the same range for your situation.
What Each Number Is Actually Measuring
Typing into the five cost fields at the top does one thing: it adds up to a single number, the extra monthly cost. Nothing else on the page reacts to these fields directly — every later calculation starts from this total, not from the individual categories. Mortgage or rent isn’t one of the fields, because that cost exists whether or not anyone else lives in the house.
Clicking Temporary Support, Learning Independence, or Financial Necessity doesn’t just relabel a card — it swaps the percentage range applied to the total above, and the contribution slider jumps to the new midpoint automatically. That’s why the range under each option is written in dollars, not just a name: it’s showing you the exact range that option would produce for your numbers.
Moving the slider on the Family Scale changes three things at once: the dollar figure above it, the tilt of the beam, and the sentence underneath. The beam tilts toward whichever side of the range’s midpoint the current number sits on, and the sentence switches between “within,” “lighter than,” or “heavier than” based on whether the number falls inside the low–high range for the purpose you picked. Typing a number into the optional income field below adds one more sentence, showing that same contribution as a percentage of what they actually earn.
The two bars further down don’t recalculate anything — they redraw. Both bars are scaled against whichever number is larger, the contribution or the market rent you entered, so the bars always show the true ratio between them rather than two disconnected percentages.
The months field changes the arrangement’s length, not the monthly amount. Two numbers update from it: the plain total (contribution multiplied by months) and the same market-rent gap from the section above, multiplied across the same stretch of time — showing what staying home adds up to save compared with renting, if the market rate stayed where you set it.
The three cards at the bottom don’t run a separate calculation. Each one is wired to move the same slider from the Family Scale section — Minimum jumps it to the low end of your current range, Full Recovery to the high end, Balanced to the midpoint. Clicking any of them updates every section above, since they all read from that one slider value.