765 ILCS 740/5 requires the landlord to provide the allocation formula in writing before demanding a proportionate tenant payment under the lease.
Under 765 ILCS 740/5, total payments under the formula for the building for a billing period may not exceed the sum demanded by the public utility.
The landlord must make the public utility bill available to the tenant upon request for a billing period for which payment is demanded.
765 ILCS 735/1.2 requires specified written disclosures and prior utility bills before leasing when the tenant-paid meter includes common-area or other-unit usage.
For a master-metered charge, start with the allocation formula
765 ILCS 740/5 applies when a lease requires a tenant to pay a proportionate share of master-metered public utility service. Before demanding that payment, the landlord must provide the tenant a written copy of the formula used to allocate public utility payments among tenants.
The formula must include all users of the public utility service and may reflect differences such as apartment size or usage. The total collected under the formula for the building during a billing period may not exceed the amount demanded by the public utility.
Request the underlying public utility bill
The Tenant Utility Payment Disclosure Act requires the landlord to make a copy of the public utility bill available to the tenant on request for any billing period for which a payment is demanded. That makes the master bill and disclosed formula the core records for testing whether an allocated charge reconciles.
A tenant-paid meter can create a different problem
765 ILCS 735/1.2 addresses a rental unit where the tenant is responsible for direct payment to the utility company but the utility meter also includes service to common areas, other units or areas used by people outside the tenant household.
Before offering the initial or renewal lease or accepting a security deposit or similar agreement, the landlord must provide a written statement describing the other areas and uses served by that meter and provide copies of the unit’s previous 12 months of utility bills unless the tenant waives the bill-copy requirement in writing.
Do not force the tenant to become the bill collector for neighbors
The same statute says the landlord may not suggest or require that the tenant collect utility money from neighboring tenants whose usage appears on the tenant’s utility-company bill. It also requires the landlord to state in writing any proposed rent reduction offered to compensate for usage outside the tenant’s unit.
A broader fee-transparency law is enacted for 2027
Illinois General Assembly materials currently display 765 ILCS 705/35 with a delayed effective date. Public Act 104-0514 moved the effective date to January 1, 2027. As of this page’s September 1, 2026 review, RentBillCheck does not apply that future rental-fee transparency section as current law.
For a lease entered on or after January 1, 2027, re-check the effective text because the new section includes broader non-optional fee and utility-inclusion disclosure rules.
Check local law too
Chicago and other Illinois municipalities can add renter protections. This page is a statewide billing baseline and should not replace a local-law check for the property address.
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Official sources
Current Illinois law requiring a written allocation formula before a landlord demands a tenant share of master-metered utility service, limiting total tenant payments to the public-utility bill and requiring the underlying bill to be available on request.
Illinois General Assembly765 ILCS 735/1.2 — Rental Property Utility Service Act ↗Current Illinois law addressing tenant-paid direct utility accounts when the tenant meter also serves common areas or other units, including written disclosure and prior-bill requirements before leasing.
Illinois General Assembly765 ILCS 705/35 — Rental fee transparency and limitations ↗Enacted Illinois rental-fee transparency section with a delayed January 1, 2027 effective date. It is future-effective as of this September 1, 2026 review.