Whole house generator installers in Missouri
Power, cost, permits & sizing ↓Missouri
68 Missouri companies install and service home standby generators, including 19 generator specialists and factory-authorized dealers. Company and brand details come from each company's own website — for warranty work, confirm current dealer status with the manufacturer directly.
68 companies
Generator specialists (5)
A & J Power Systems Generator specialist
Braco Generators, LLC Generator specialist
Generator Supercenter of St. Louis Generator specialist
PCS Electronics LLC Generator specialist
Southeast Services Generator specialist
Electrical contractors that install generators (30)
All Electric Electrical contractor
Amplify Electrical Services Electrical contractor
Anytime Electric Electrical contractor
Arnwine Electric & Home Inspections Electrical contractor
Braco Electrical & Contracting, LLC Electrical contractor
Brda Electric Electrical contractor
Cain Electric Electrical contractor
CAS Electric Electrical contractor
Compass Electric LLC Electrical contractor
Current Solutions Electric Electrical contractor
Eric Kjelshus Energy Heating and Cooling Electrical contractor
Freedom Electric Electrical contractor
Grasser Electric & Home Services Electrical contractor
J. Bathe Electric Electrical contractor
JB Electric Electrical contractor
Joplin Industrial Electric Electrical contractor
Legacy Electric Electrical contractor
Marshall Electric Inc Electrical contractor
MidStates Energy Co. Electrical contractor
Midway Electric Electrical contractor
Mundwiller Electric Electrical contractor
Potts Electric Electrical contractor
Power Tech Electric LLC Electrical contractor
Pure Light Electric LLC Electrical contractor
R & R Electrical Company Inc Electrical contractor
Randolph Electrical Contracting LLC Electrical contractor
Reinhold Electric, Inc. Electrical contractor
rYse electric LLC Electrical contractor
SmartPower Services Electrical contractor
Thompson Electrical Installation Electrical contractor
HVAC & plumbing contractors that install generators (19)
A.B. May Heating, A/C, Plumbing & Electrical HVAC / plumbing contractor
Academy Air Heating, Cooling, Plumbing and Electric HVAC / plumbing contractor
Air Services Heating, Cooling, Plumbing, and Electrical HVAC / plumbing contractor
Aire Solutions HVAC / plumbing contractor
Aire Solutions – Cape Girardeau HVAC / plumbing contractor
All Klear HVAC / plumbing contractor
Butler Heating & Air HVAC / plumbing contractor
Chesterfield Service HVAC / plumbing contractor
Current Inc. HVAC / plumbing contractor
Dutch Enterprises HVAC / plumbing contractor
Hoffmann Brothers HVAC / plumbing contractor
Home HVAC, Plumbing & Electrical HVAC / plumbing contractor
Kallmeyer Services LLC HVAC / plumbing contractor
Lee's Summit Heating & Cooling HVAC / plumbing contractor
Lorenz Plumbing Heating & Air Conditioning HVAC / plumbing contractor
Lundy Heating & Cooling and Jaymac Equipment HVAC / plumbing contractor
Precision Heat & Air, Inc. HVAC / plumbing contractor
Presley Sales & Service HVAC / plumbing contractor
Sherman Heating, Air Conditioning, Plumbing, and Appliances HVAC / plumbing contractor
Power in Missouri
Missouri sits at a severe-weather crossroads where ice, wind, and polar-vortex grid stress all take the power out. The January 2007 ice storm coated the southwest of the state in about an inch and a half of ice and left more than 200,000 people without power, some for days to weeks. The region's tornadoes are among the deadliest in the country — the May 2011 Joplin EF5 killed 161 people and destroyed or damaged some 8,000 homes and buildings, and a May 2019 EF3 tore a nineteen-mile path through the state capital. And in February 2021 the regional grid operator declared its first-ever top-level energy emergency and directed Missouri utilities to run controlled rolling blackouts during the deep freeze. A whole-home standby generator starts on its own within seconds and carries the furnace, the well pump, the sump pump, and the refrigerator on natural gas or propane until the line comes back.
Generator permits & codes in Missouri
- Who issues permits
- Missouri has no statewide building code and no state residential electrical or contractor license — regulation of a generator install is left entirely to local government. Kansas City, the City of St. Louis, St. Louis County, Springfield, and Columbia each run their own permit and licensing programs, and requirements differ between them; some unincorporated county areas require no permit at all. The practical first step is to confirm the specific authority having jurisdiction before any work begins.
- Timeline
- Varies by jurisdiction, more so than in most states. Incorporated cities require electrical (and usually gas or mechanical) permits with inspection; some unincorporated areas have no permit process at all, though licensed, inspected work is still the right standard for safety and insurance.
- Code in force
- Because there is no statewide code, the enforced edition of the National Electrical Code depends on the authority having jurisdiction. Kansas City enforces the 2017 NEC (effective June 28, 2020), and the City of St. Louis likewise lists the 2017 NEC alongside the 2018 IBC and IMC. Editions vary and can lag between neighboring jurisdictions, so confirm the current edition with the local building department.
- Major utilities
- Ameren Missouri, the state's largest electric utility, serves central and eastern Missouri including greater St. Louis. Evergy serves the Kansas City area and western Missouri through its Missouri Metro and Missouri West divisions. Liberty (the Empire District Electric Company) serves the southwest around Joplin, and rural electric cooperatives cover much of the countryside; natural gas is delivered chiefly by Spire. All the investor-owned utilities are regulated by the Missouri Public Service Commission. A permanently installed generator must isolate from the grid through a transfer switch so it can never backfeed the lines and endanger repair crews.
- Worth knowing
- Missouri is one of only a handful of states with no statewide building code and no state electrical or contractor license — building and electrical regulation is delegated entirely to local government. That means the permit requirement, the license your contractor must hold, and even the NEC edition you're inspected against can all change when you cross a city or county line, and some unincorporated areas require no permit at all. Verifying your specific local authority is the single most important step before a generator install here.
Common questions about whole house generators in Missouri
How much does a standby generator cost installed in Missouri?
For a typical home, budget roughly $10,000–$18,000 all-in for a
whole-house air-cooled standby unit (about 18–26 kW): the
generator, the automatic transfer switch, the pad, the fuel hookup, the
electrical work, and any permit fees. An essentials-only unit
(10–14 kW) runs about $6,000–$10,000. Homes in the metros usually
run on natural gas, while rural properties use a propane tank that adds
to the up-front cost — and on propane it's worth sizing the tank for the
multi-day runtime an ice storm can demand. A panel upgrade or a long
fuel-line run moves the number.
Do I need a permit to install a generator in Missouri?
It depends entirely on where you live, because Missouri has no
statewide building code and no state electrical license — regulation is
left to local government. In the incorporated cities you will need an
electrical permit (and usually a gas or mechanical permit) with an
inspection, and the city defines the license your contractor must hold.
In some unincorporated county areas there may be no permit requirement
at all. Either way, licensed, code-compliant, inspected work is the
right standard for safety and insurance, so the first step is always to
confirm the rules with your local authority having jurisdiction.
What size generator do I need in Missouri?
That comes down to a load calculation any good installer runs during
the site visit, and Missouri's climate pulls from both directions. Hot,
humid summers make central air conditioning the single largest load,
with a compressor start-up surge that sets a floor on capacity. Cold
winters bring furnace blowers, heat pumps, and electric-resistance
backup heat. Rural and flood-prone properties add well pumps and sump
pumps as must-run loads. Essentials only fits in 10–14 kW; a
typical whole house lands at 18–26 kW; a soft-start on the AC can
keep the unit, and the price, smaller.
Generac, Kohler, Cummins, or Briggs & Stratton — does the brand matter?
All four make reliable home standby units; the installer and the
service relationship afterward matter more than the badge. Generac has
the largest dealer network in the state, so parts and warranty techs are
easy to find from the western metro across to the eastern metro and down
into the Ozarks; Kohler and Cummins have strong dealers in the larger
cities. A factory-authorized dealer can perform warranty service on its
own brand, which is worth weighing when two brands otherwise look alike.
Use the brand pages here to see who installs and services each one near
you.
How long does installation take?
The on-site work is usually one to two days once the unit is in hand:
set the pad, run the gas and electrical, mount the transfer switch, and
commission it. The calendar time is longer — a site visit and quote,
then permitting where it's required, then the inspection. After a major
ice storm or tornado outbreak those steps stretch, because every house
in the county wants a generator and an installer at the same moment.
Ordering ahead of storm season, rather than the week after an outage, is
how you avoid competing for both the unit and the crew.
What maintenance does a standby generator need?
An annual service — oil and filter, spark plugs on schedule, a battery
check, and a load test — on top of the weekly self-test the unit runs
on its own. Cold winters are hard on the starting battery, and the
humid summers are hard on the enclosure, so a unit that sat idle through
a mild stretch still needs to prove it will start before the season it's
needed. Homes on propane should confirm tank level ahead of an ice-storm
stretch. Many installers listed here offer maintenance plans, and
several service brands they don't sell.