Someone was away for a month. Who pays the electric bill?
Rent doesn’t change when you travel, but usage does. Split the part of the bill that follows use by days at home, and keep the fixed charges even.
Meter and service charges, the fridge, the router: what the bill costs even when nobody is home.
Sep 1, 2026 to Sep 30, 2026 · 30 days
| Person | Days home | Fixed part | Usage part | Pays |
|---|---|---|---|---|
| Ana | 30 / 30 | $15.50 | $69.75 | $85.25 |
| Ben | 30 / 30 | $15.50 | $69.75 | $85.25 |
| Cam | 0 / 30 | $15.50 | $0.00 | $15.50 |
| Total | $46.50 | $139.50 | $186.00 |
“Make it a household” signs you in, adds this bill to a new household ledger, and sets it up as a monthly bill you can edit.
The numbers, step by step
The September electric bill is $186. Cam was away the whole month; Ana and Ben were home all 30 days. The household agreed that about a quarter of the bill is fixed (the fridge, standby devices and the meter charge run whether anyone is home), so that quarter is split three ways and the rest by days home.
- Ana pays $85.25 ($15.50 fixed + $69.75 usage): home 30 of 30 days (50% of the usage) + an even share of the fixed 25%.
- Ben pays $85.25 ($15.50 fixed + $69.75 usage): home 30 of 30 days (50% of the usage) + an even share of the fixed 25%.
- Cam pays $15.50 ($15.50 fixed + $0.00 usage): home 0 of 30 days (0% of the usage) + an even share of the fixed 25%.
- Total: $186.00 for 30 days.
Names and amounts are samples. Change any number in the calculator above and the result updates.
A fairness test you can run together
Fair-division research calls a split envy-free when each person feels they got the best piece “in her own estimation”, as Francis Su puts it. Ask: at these prices, would anyone rather swap rooms? If not, nobody envies anyone. Bid mode makes that a guarantee.
Keep it running
Turn this into a household: rent posts at the agreed split each month, bills split by days home, and housr works out who owes whom. Roommates join with a link and a name.
Make it a householdWhen this split is fair, and when it isn’t
Fair when
- The bill really does follow use: heating and cooling a home are among the largest uses of household electricity, and nobody heats an empty room for the person who is away.
- Someone who is away still keeps their room, their things and the right to come back, so a small fixed share for them is reasonable.
- Days away are agreed and written down before the bill arrives, so nobody is reconstructing travel dates from memory.
Not so fair when
- For a weekend away, the arithmetic isn’t worth the conversation; most households only adjust for absences of a week or more.
- If the person away left a space heater or a gaming PC running, days home understate their usage; the fixed share is the place to account for that.
- Internet and streaming don’t vary with presence. Keep them out of a presence split (see the internet scenario).
This is general information about splitting costs between yourselves, not legal advice. Your lease and your state’s law decide what you owe the landlord.
Sources
- U.S. Energy Information Administration, Electricity use in homes. Checked 2026-10-05.
- U.S. Energy Information Administration, How much electricity does an American home use?. Checked 2026-10-05.
- Francis Su, Harvey Mudd College, Fair Division Calculator (historical page). Checked 2026-10-05.
Related situations
One of you works from home. Should they pay more for utilities?
A home office runs heating or cooling, lights and a computer through the day. That is real use, but often smaller than people fear. Put a number on it and see.
Open the example Split rentInternet for all, streaming for some
Internet is a household utility; a streaming subscription is a choice. Split each one among the people who actually use it.
Open the example Split rentA roommate is leaving mid-lease. What do they owe, or get back?
Three separate questions get tangled when someone leaves: this month’s rent, their share of the deposit, and the last bills. Answer them one by one and net them into a single payment.
Open the example