Missouri · Illinois · #23 metro by population

Home energy audits in St. Louis

Where to get a home energy audit in the St. Louis area, what it costs, which rebates are open now and where Missouri and Illinois stand on the federal Home Energy Rebates. Every program links to its official page and was checked on October 12, 2026.

Metro area: St. Louis, MO-IL Metropolitan Statistical Area.

A red blower-door panel with a large fan fitted into the front doorway of a brick bungalow, a pressure gauge on a stool inside
Start here Free Ameren Missouri CommunitySavers single-family (income-eligible), with Spire · Income-qualified
Rebates and incentives open now 3 of 5 1 closed or fully reserved; 1 unconfirmed or not open yet
Federal Home Energy Rebates Not open yet What that means here

St. Louis at a glance

Climate zone 4A

IECC 2021 climate zone for St. Louis city, MO. PNNL ↗

Heating and cooling 4,433 HDD · 1,713 CDD

Heating and cooling degree days, base 65°F, 1991–2020 normals at ST LOUIS LAMBERT INTL AP, MO US (USW00013994). NOAA ↗

Homes 1939 or earlier median year built

The Census puts the median in its lowest category, “built 1939 or earlier.” 45.3% of occupied homes are owner-occupied. St. Louis city, Missouri, 2020–2024 ACS 5-year. Census ↗

Radon EPA zone 2

moderate potential: predicted average 2–4 pCi/L (St. Louis city, MO). EPA says not to use the zone to decide whether to test: high levels turn up in all three zones, so test every home. Radon testing guide · EPA ↗

What energy costs here

State Electricity¢ per kWh · July 2026 Natural gas$ per therm · 2025 average Heating oil$ per gallon · week of Oct 5, 2026 Propane$ per gallon · week of Oct 5, 2026
Missouri 16.1¢ $1.44 $14.94 per thousand cu ft Not reported $2.06
Illinois 19.2¢ $1.09 $11.25 per thousand cu ft Not reported $1.83
  • Electricity: EIA’s average residential price, July 2026 (preliminary; released September 24, 2026). The U.S. average was 18.3¢ per kWh. EIA ↗
  • Natural gas: EIA’s 2025 average residential price per thousand cubic feet, which EIA says includes taxes and delivery, divided by 10.36 therms per thousand cubic feet (EIA’s 2025 average heat content of 1,036 Btu per cubic foot). A full-year average is used because summer months run far higher. EIA ↗
  • Heating oil and propane: EIA’s weekly residential prices, excluding taxes, for the week of October 5, 2026. EIA surveys them only in some states. EIA ↗

Utilities in the St. Louis area

Utility efficiency programs follow the company that delivers your power or gas, so check your bill before you book anything.

Electric

  • Ameren Missouri Electric service on the Missouri side, including St. Louis City. Ameren calls itself 'the largest electric power provider in Missouri', and the City's 2025 climate plan names 'the investor-owned utilities Ameren and Spire' as the city's suppliers. Source ↗
  • Ameren Illinois Ameren's Illinois utility, the main electric and gas provider on the Illinois side of the metro. Its programs run through AmerenIllinoisSavings.com. County-level boundaries were not checked. Source ↗

Natural gas

  • Spire (Spire Missouri, 'Eastern Missouri' region) Natural gas for St. Louis City and County. Spire's site maps ZIP codes beginning 630-639 to its 'Eastern Missouri' region. Source ↗
  • Ameren Illinois (gas) Natural gas on the Illinois side of the metro. Ameren Illinois 'ranks as Illinois' third largest natural gas distribution operation'. Source ↗

Most St. Louis-area homes on the Missouri side have Ameren Missouri electricity and Spire gas, and the two run the income-qualified CommunitySavers program together. Ameren Missouri's electric programs (PAYS, HVAC PAYS) don't apply in Illinois; Illinois-side homes use AmerenIllinoisSavings.com instead. Cooperative and municipal utilities in the outer counties were not checked.

How to get a home energy audit in St. Louis

4 programs in our research, open ones first. Prices are as each program publishes them. If you want a full diagnostic audit outside these programs, look for a certified auditor: how to find one and what audits cost.

Ameren Missouri CommunitySavers single-family (income-eligible), with Spire

Ameren Missouri in partnership with Spire

Open Open. 'The program operates through December 31, 2026; however, incentives are dependent on available funds.'
Free Income-qualified

Official page ↗ · verified October 12, 2026

Who qualifies
Active Ameren Missouri electric account in a building with four or fewer units. The household must also (1) be in subsidized housing, (2) have income at or below 80% AMI or 200% of the federal poverty level, or (3) live in an area Ameren designates as high need.
What you get
An Energy Advisor assessment (about 2 hours) with immediate installs, and possibly later upgrades taking half a day to two days. Items can include HVAC upgrades, efficient showerheads and aerators, ENERGY STAR refrigerators, LED lighting and attic insulation.
How to book
Use the inquiry form on the Ameren CommunitySavers page or call 1.877.215.5752.

Ameren Illinois Home Energy Assessment (Illinois side of the metro)

Ameren Illinois Energy Efficiency Program

Open Open as of 2026-10-12. The printable application is labeled 2026.
Free

Cost, as published Free for eligible income-qualified households. Other customers get the assessment through a Program Ally contractor; Ameren's page does not state that price.

Official page ↗ · verified October 12, 2026

Who qualifies
Free track: single-family homes heated with Ameren Illinois gas or electricity (or Ameren electric customers heating with propane) who meet income limits. Renters in single-family homes or duplexes need owner consent.
What you get
An Energy Advisor assessment with free install of LEDs, faucet aerators and an advanced power strip. Insulation, air sealing and ventilation upgrades may follow at little or no cost.
How to book
Check eligibility online at il-aleet.com or use the printable application from AmerenIllinoisSavings.com.

Missouri Certified Home Energy Auditor directory

Missouri Department of Natural Resources, Division of Energy

Unconfirmed Directory published as of 2026-10-12
Set by each auditor Directory

Cost, as published Set by each auditor (private service)

Official page ↗ · verified October 12, 2026

Who qualifies
Any Missouri homeowner. Listed auditors 'may provide services anywhere in Missouri.'
What you get
A state list of all Missouri Certified Home Energy Auditors. Inclusion is not an endorsement.
How to book
Contact auditors directly from the DNR directory

Ameren Missouri Pay As You Save (PAYS) free home energy assessment

Ameren Missouri

Closed Closed for 2026. Ameren Missouri says 'Whole Home PAYS and FastTrack HVAC PAYS are no longer accepting enrollments for 2026' and that the program 'has been fully subscribed for 2026.' No reopening date is given.
Free

Cost, as published Free and 'no-obligation'. Upgrades are paid off through a fixed monthly charge on the electric bill, which includes 3% interest and a small close-out fee. Ameren says 'This is not a loan'. There is no credit check, the charge stays with the meter, and it must be no more than 80% of estimated monthly savings, or a copay is offered.

Official page ↗ · verified October 19, 2026

Who qualifies
All Ameren Missouri residential electric customers. Renters need written owner consent. Mobile homes must be on a permanent foundation and no more than 35 years old. Not available to Illinois customers.
What you get
A visit from a trained energy expert who recommends upgrades. Typical upgrades are HVAC, attic insulation, duct sealing, air sealing and LED lighting, installed with little or no upfront cost.
How to book
Complete the PAYS interest form linked from the Ameren PAYS page. Ameren then calls to schedule. The phone number for questions is 1.800.563.2105.

Rebates and incentives now

5 offers in our research for the St. Louis metro; 3 are open as of October 12, 2026. Many require the program’s own contractor or an audit first, so read the terms before you buy.

Insulation and air sealing 1 open of 1

Ameren Illinois insulation discounts (Illinois side)

Ameren Illinois Energy Efficiency Program

Open Open for 2026

Official page ↗ · verified October 12, 2026

Amount 2026 discount rates: attic insulation $1.10 per sq ft, wall insulation $1.10 per sq ft, rim joist insulation $2.00 per linear ft

Who qualifies Eligible Ameren Illinois customers. Work goes through a Program Ally contractor after a Home Energy Assessment.

Heat pumps 0 open of 1

Ameren Missouri PAYS heating and cooling rebates (2026)

Ameren Missouri

Closed Closed for 2026. Ameren Missouri says 'Whole Home PAYS and FastTrack HVAC PAYS are no longer accepting enrollments for 2026' and that the program 'has been fully subscribed for 2026.' No reopening date is given.

Official page ↗ · verified October 19, 2026

Amount Air-source heat pump at 15.2+ SEER2 (replacing a heat pump, replacing electric resistance, or where there's no central system): $2,000 per system. Dual-fuel air-source heat pump at 15.2+ SEER2: $2,000 per system. Ground-source heat pump at 23+ EER: $5,000 per system. Mini-split AC or heat pump at 19+ SEER2: $500 per ton. Central AC at 15.2+ SEER2: $1,000 per system. Smart thermostat: $250.

Who qualifies Ameren Missouri electric customers enrolled in 'tier 4 of the PAYS program' who have lived in the home for the past 12 months. Homes with existing non-electric heat 'must maintain that heat source (as primary or backup)', and Ameren 'does not promote fuel switching'. No new construction. AC replacements must meet failure, age or 14-SEER-or-less conditions.

Appliances and equipment 1 open of 2

Spire Missouri (Eastern Missouri) natural gas appliance and insulation rebates

Spire

Open Open as of 2026-10-12. The Missouri form dated 10/2025 says a rebate 'can be obtained up to one year after the purchase and installation'.

Official page ↗ · verified October 12, 2026

Amount Gas furnace: $300 at 96%+ AFUE, $200 at 92% to under 96%. Gas boiler at 90%+: $300. Combined space and water heating at 90%+: $450. Tankless water heater (0.80+ UEF): $300. Storage water heater: $200 for 20-55 gal (0.64+ UEF), $350 for 55-100 gal (0.76+ UEF). Attic, ceiling or floor insulation to R38 or more: $0.40 per sq ft up to $750. Programmable thermostat: $25 or 50% of cost, whichever is lower. Smart or Wi-Fi thermostat: $75.

Who qualifies Residences with an active Spire account. A licensed HVAC or plumbing contractor must install the equipment; only thermostats may be self-installed. Rebates are paid as a prepaid card.

Missouri Show Me Green Sales Tax Holiday

Missouri Department of Revenue

Unconfirmed Annual, 'begins April 19 and continues through April 25'. The 2026 window has passed; the next is April 19-25, 2027.

Official page ↗ · verified October 12, 2026

Amount Qualifying ENERGY STAR certified new appliances are exempt from 'all state and local sales and use taxes' during the holiday

Who qualifies Purchases in Missouri during the holiday window

Financing 1 open of 1

Illinois Energy Efficiency Loan Program: Ameren Illinois on-bill financing (Illinois side)

Energy Finance Solutions with Ameren Illinois

Open Listed as available as of 2026-10-12. The ComEd shutdown notice on the same site does not apply to Ameren.

Official page ↗ · verified October 12, 2026

Amount $500-$20,000 unsecured at 7.49% fixed for 1-10 years (7- and 10-year terms need loans over $8,000), repaid on the utility bill

Who qualifies Ameren Illinois customers in 1-4 unit homes, condos and mobile homes whose accounts meet utility eligibility standards

Statewide rebate programs and federal options: rebates and programs.

Heat pumps in St. Louis → What one costs to run against gas here, each heat pump rebate with the equipment rule that decides which models qualify, and the certified systems and brands that suit the climate.

Federal Home Energy Rebates in Missouri and Illinois

The two federal rebate programs, HOMES (whole-home efficiency) and the high-efficiency electric home rebates (HEAR, renamed HEEHR in 2026), are run by each state, so availability depends on the state. DOE rewrote the rules effective May 29, 2026 (Program Notice 26-2 ↗): no more federal rebates for switching from gas, oil or propane to electric equipment, and insulation and air sealing come before heating and cooling upgrades unless a home already meets a state-set level.

Status for the St. Louis metro
Not open yet not launched (as of 2026-10-12). Missouri says rebates 'may not be made available until 2027 at the earliest and potentially as late as 2028'. Illinois side also not launched (pending USDOE approval). Official page ↗ verified October 12, 2026

Program: Missouri IRA Home Energy Rebates: HOMES and HEEHR/HEAR (Sections 50121 and 50122)

Run by: Missouri Department of Natural Resources, Division of Energy, with the Environmental Improvement and Energy Resources Authority (EIERA) procuring an implementer

Missouri expects $76 million for HOMES and $75 million for HEEHR. DNR submitted its application to DOE on November 22, 2024. DNR says details 'are not finalized', it 'cannot provide an estimate as to when rebates will be available', and 'The rebates may not be made available until 2027 at the earliest and potentially as late as 2028.' Rebates are expected to stack with utility rebates. On the Illinois side, Illinois EPA's HOMES and HEAR also have not launched ('The program launch is pending USDOE approval').

StateHEAR / HEEHR (electric appliances)HOMES (whole-home efficiency)
Missouri Missouri rebate guide
Not open yet not launched (state says rebates may not be available until 2027 at the earliest, possibly 2028) Official page ↗ verified October 12, 2026
Not open yet not launched (same timeline) Official page ↗ verified October 12, 2026
Illinois Illinois rebate guide
Not open yet not launched (state says its HEAR application has not yet been processed by DOE) Official page ↗ verified October 12, 2026
Not open yet not launched (pilot pending DOE approval) Official page ↗ verified October 12, 2026

How the programs work: Home Energy Rebates explained · every state’s status.

Help for lower-income households

Missouri Low-Income Weatherization Assistance Program

Missouri DNR Division of Energy through 18 local agencies. St. Louis City: Urban League of Metropolitan St. Louis, 314-615-3600. St. Louis County: Community Action Agency of St. Louis County, 314-863-0015. St. Charles, Lincoln and Warren: North East Community Action Corp. (NECAC), 573-324-2231. Franklin and Jefferson: Jefferson-Franklin Community Action Corp., 636-789-2686.

Free cost-effective efficiency work for eligible low-income households. You apply to your local agency with income documents, an agency auditor does an energy audit, a crew or contractor installs the measures, and a quality-control inspection follows. DNR points to DOE poverty guidelines for income limits.

Official page ↗ · verified October 12, 2026

CommunitySavers (Ameren Missouri and Spire)

Ameren Missouri and Spire

Single-family: free assessment and upgrades for households at or below 80% AMI or 200% FPL, in subsidized housing, or in high-need areas (runs through December 31, 2026, subject to funds). Multifamily (3+ units, Spire gas plus Ameren Missouri electric, natural-gas heating or water heating): free programmable thermostats, aerators, showerheads, pipe wrap, and furnace check-ups and cleanings.

Official page ↗ · verified October 12, 2026

Illinois Home Weatherization Assistance Program (Metro East)

Illinois DCEO through local agencies. Madison County: Madison County Community Development. St. Clair County: St. Clair County Community Action Agency. Monroe: Western Egyptian Economic Opportunity Council. Jersey, Macoupin and Calhoun: Illinois Valley Economic Development Corporation. Clinton and Bond: BCMW Community Services.

Free weatherization up to $20,000 per home for households at or below 200% of the federal poverty level (see the Chicago entry for IHWAP details).

Official page ↗ · verified October 12, 2026

Ameren Illinois income-qualified Home Energy Assessment and upgrades

Ameren Illinois

Free assessment, free installed products, and insulation, air sealing and ventilation upgrades at little or no cost for income-qualified single-family households. Work is done by Program Allies.

Official page ↗ · verified October 12, 2026

Local energy rules

None of the 2 rules we found reach ordinary homes.

Not for ordinary homes

City of St. Louis Building Energy Awareness Ordinance (benchmarking, Ord. 70474, 2017)

Who it applies to Large buildings only: 50,000 sq ft and above. Ordinary homeowners are not affected.

Requires 'buildings that are 50,000 square feet and above to report energy and water data annually to the City'. The City's 2025 Sustainability and Climate Plan proposes extending benchmarking to buildings of 25,000 sq ft by 2031 and 10,000 sq ft by 2036. That is a plan strategy, not law yet.

Official page ↗ · verified October 12, 2026

Not for ordinary homes

City of St. Louis Building Energy Performance Standard (BEPS, Ord. 71132)

Who it applies to Large commercial, multifamily, institutional and municipal buildings of 50,000 sq ft and above. Ordinary homeowners are not affected.

Passed 26-0. Ordinance 71132 took effect June 4, 2020. Covered buildings must cut energy use to meet performance standards by building type (first compliance 'by May 2025'), reviewed every four years and tracked in ENERGY STAR Portfolio Manager.

Official page ↗ · verified October 12, 2026

Notes worth knowing

  • Missouri's IRA rebates won't arrive before 2027 'at the earliest', possibly 2028, and Illinois' are also unlaunched, so neither side of the metro has state IRA rebates.
  • Ameren Missouri's PAYS assessment is free to all residential electric customers with no income test, unlike ComEd in Chicago.
  • Its 2026 heat pump rebates are large ($2,000 air-source, $5,000 ground-source) but tied to PAYS tier 4, and gas-heated homes must keep gas heat as backup.
  • Ameren says PAYS is fully subscribed for 2026 and no longer accepting enrollments.
  • CommunitySavers runs only through December 31, 2026 as published.

What our research couldn’t confirm

  • St. Louis County (outside the City) energy rules were not checked.

St. Louis: common questions

How do I get a home energy audit in St. Louis?

Start with Ameren Missouri CommunitySavers single-family (income-eligible), with Spire. Run by: Ameren Missouri in partnership with Spire. It’s for income-qualified households. Cost: Free. Who qualifies: Active Ameren Missouri electric account in a building with four or fewer units. The household must also (1) be in subsidized housing, (2) have income at or below 80% AMI or 200% of the federal poverty level, or (3) live in an area Ameren designates as high need. How to book: Use the inquiry form on the Ameren CommunitySavers page or call 1.877.215.5752. Our research lists 4 audit programs for the St. Louis metro, checked October 12, 2026; all of them are on this page.

Are the federal Home Energy Rebates available in St. Louis?

Not launched (as of 2026-10-12). Missouri says rebates 'may not be made available until 2027 at the earliest and potentially as late as 2028'. Illinois side also not launched (pending USDOE approval). Checked October 12, 2026. Nationally, DOE rewrote the rules effective May 29, 2026: federal appliance rebates no longer pay for switching from gas, oil or propane to electric equipment, and homes must get insulation and air sealing before heating and cooling upgrades unless they already meet a state-set level.

Is there help for lower-income households in St. Louis?

Yes. Programs for income-qualified households in the St. Louis metro include Missouri Low-Income Weatherization Assistance Program, CommunitySavers (Ameren Missouri and Spire), Illinois Home Weatherization Assistance Program (Metro East) and Ameren Illinois income-qualified Home Energy Assessment and upgrades. Each one’s rules and contacts are listed on this page, with a link to its official page.

Which local energy rules affect homeowners in St. Louis?

No local energy rule in our research applies to ordinary existing homes. 2 rules apply only to larger buildings.

Can I claim a federal tax credit for an energy audit in St. Louis?

Not for an audit done in 2026. The federal credit of up to $150 for a home energy audit was part of the Energy Efficient Home Improvement Credit (25C), and the IRS says it can’t be claimed for audits paid for or done after December 31, 2025. Public Law 119-21 ended 25C and the Residential Clean Energy Credit (25D) for 2026 work. An audit done in 2025 is claimed on the 2025 return (Form 5695).

Sources

Every source below was opened and checked on October 12, 2026.

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