Utility Bill Prorate Calculator

1. Find the billing period dates and the day count printed on the bill.
2. Count the days you were responsible for the service during that period.
3. Divide the bill by the number of days in the period to get the daily cost.
4. Multiply the daily cost by your days to get your share.

The calculator does the last two steps for you: enter the full bill, the total days in the period, and the days you were there.

A utility bill usually has two parts: a fixed charge that is the same every period, and a usage charge that depends on how much electricity, gas, or water you used.

Prorating by days is exact for the fixed charge, but for the usage charge it assumes you used the same amount each day. That is often untrue in very hot or cold months, when heating and cooling drive most of the bill.

If a meter reading was taken on the move date, split the usage charge by the reading and prorate only the fixed charge by days. Example 2 below works through this. To estimate a month's usage charge before you split it, use the Utility Bill Estimator.

Before you move, contact each utility, ask them to stop service in your name on a set date, request an actual final meter reading, and give a forwarding address for the final bill. Write down the date and the name of the person you spoke with.

If the meter cannot be read, the final bill may be an estimate and can be corrected later. If you are moving in, confirm that a final reading was taken for the previous occupant so your first bill starts from the right point.

Monthly utility billing periods are usually between 26 and 35 days, and the exact count is printed on the bill, so use that number rather than a calendar month. A first or final bill can be shorter or longer.

Count days inclusively when both end dates belong to the same person. For example, a period from January 15 through February 14 counted with both end dates is 31 days: 17 days in January (the 15th through the 31st) plus 14 days in February.

Your lease or written agreement should state whether the move day counts, and both parties should use the same rule so no single day is paid for twice.

When the account is in the landlord's name, a tenant's share for a partial period is usually worked out the same way, but the lease controls who pays which utilities.

Some places limit how a landlord can charge tenants for a share of a single building meter, so check your lease and local rules before billing or paying such a charge. This is general information, not legal advice.