How siblings can split a parent's care costs fairly

How do siblings split a parent’s care costs?

Agree on one basis before the first bill, write it down, and record every cost in one place. This page covers the arithmetic of sharing costs that siblings have chosen to share. It does not say who must pay for a parent’s care. That question, and anything about taxes, benefits, medical decisions or who controls a parent’s money, is for a lawyer or a financial adviser, and it is outside this page.

Start with the parent’s own money. List what it already covers and record it apart from the siblings’ shared costs, so the shared record holds only what the siblings pay.

What is a monthly cost and what is a one-off?

Treat steady costs as one monthly amount and everything else as a separate expense. Say the steady costs are $1,500 for an aide and $900 for a monthly facility fee, which makes $2,400 a month. Those two go in as one repeating expense.

A $450 repair, a $120 copay or a flight to visit goes in once, on the day it happens, with the same split rule applied to it.

Which basis should the siblings use?

Here are four bases on the same $2,400. Say the siblings earn $90,000, $60,000 and $30,000 a year, and Sibling C makes the visits.

Basis	Sibling A	Sibling B	Sibling C	Cash total
Equal	$800.00	$800.00	$800.00	$2,400.00
By income (50%, 33.3%, 16.7%)	$1,200.00	$800.00	$400.00	$2,400.00
Agreed percent (40%, 40%, 20%)	$960.00	$960.00	$480.00	$2,400.00
Income, with credit for C’s time	$1,400.00	$933.33	$66.67	$2,400.00

Equal. $2,400 divided by 3 is $800 each. It is the simplest rule and the one that ignores differences in income.

By income. The incomes add to $180,000, so Sibling A’s share is 90 over 180, or 50%, and Sibling B’s is 33.3%. Sibling C’s is 16.7%. Of $2,400 that is $1,200, $800 and $400. Splitting bills by income shows the formula step by step.

An agreed percent. The siblings can pick percentages that do not follow income exactly, such as 40, 40 and 20. That gives $960, $960 and $480. Every percentage works as long as the three add to 100.

Income with credit for time. Sibling C does the visits, 20 hours a month. At a rate the three agree on, say $20 an hour, that is $400 of work. Add it to the pool, so the pool is $2,400 + $400 = $2,800, and split the pool by income: $1,400, $933.33 and $466.67. Sibling C has already given $400 of time, so C’s cash share is $466.67 minus $400, which is $66.67. The cash still adds to $2,400, because $1,400 + $933.33 + $66.67 is $2,400.00. The rate for time is the siblings’ choice, so fix it in writing as well.

How do you settle one-off costs and monthly ones together?

Add everything to one running balance and settle once a month. Say Sibling A pays the aide ($1,500), Sibling B pays the facility fee ($900) and the repair ($450), and Sibling C pays nothing yet. The month’s costs are $2,850.

1. Work out each share by income. Of $2,850, A’s share is $1,425, B’s is $950 and C’s is $475.
2. Compare it with what each person paid. A paid $1,500, which is $75 more than A’s share. B paid $1,350, which is $400 more than B’s share. C paid $0, so C owes $475.
3. Settle. C pays $75 to A and $400 to B, which covers the $475.

How do you set it up in EvenOut?

EvenOut keeps the running balance, so the monthly cost and the one-offs end up in the same group.

1. Make a group. Tap “New group”, choose “Household” (“Rent and bills”) or “Other” (“Anything else”), and name it.
2. Add your siblings. In group settings, open “Members”, then “Add people”. Friends can be added directly, “Add a guest” tracks a sibling who is not on EvenOut yet, and anyone else joins through “Invite with a link”.
3. Add the monthly cost. Tap “Add expense”, type $2,400, describe it and set who paid (“Who paid?” lists every member). Tap the split chip and choose “Exact amounts” to type $1,200, $800 and $400, or “Percent” to type 40, 40 and 20. The pill reads “All assigned” or “Adds up to 100%”.
4. Repeat it. Open “Photo, repeat, pending or note”, tap “Repeat” and choose “Monthly”. The expense you save counts as the first. The server then adds every following month as an ordinary expense, paid by the same person and split the same way, at around 9:00 in your time zone. You need a connection to set it up. If the cost changes, stop the repeat under “Repeating expenses” and add a new one.
5. Choose who can edit. The owner can set “Who can edit” in group settings to “Only their own”, so people change only what they added or paid for.
6. Settle up. Tap “Settle up” when a sibling pays. It records the payment and does not move money. The group’s “Balances” list shows your balance with each person.

What should you do next?

Write down the basis, the monthly total and who pays what, and set a date to review it. Care costs change, and a basis that fits this year may not fit next year.

For the formulas, how to split by percentage and the income split calculator work out any basis you choose. Splitting childcare costs between parents covers another recurring family cost, and how to track shared expenses covers keeping the record. The family expense tracker template gives a printable version.