Ameren (AEE)
Regulated power, gas, and transmission utility serving Missouri and Illinois.
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Ameren keeps the lights on and the furnaces lit across Missouri and downstate Illinois. It does not win customers; a regulator sets the price, and Ameren earns a return on the poles, wires, pipes and power plants it builds. That is why the story now is construction: data-center campuses are arriving, and Ameren is building power plants and wires years ahead of the bills they will send.
Item facts: FY2025 · year ended Dec 31, 2025, from filings, earnings calls and company pages.
Judgment weights, not filed revenue
The band summarizes business focus and direction. ~ marks estimates.
6 in detail · 13 more below
Ameren Missouri
Ameren's biggest piece: it burns the fuel, spins the turbines and runs the wires to 1.3 million homes and businesses around St. Louis. $4,795M of revenue and $747M of profit in FY2025, plus $2.5B of construction — most of the company's. Watch the request to raise rates in mid-2027.
Competes with Evergy Missouri West electricity (Evergy) · Power plants built on the customer's own site (Independent power producers)
In plain English
One company owns the whole chain here, from the fuel pile to the lamp on the table. Ameren Missouri runs coal, nuclear and gas plants around greater St. Louis, carries that power over its own lines, and bills the household at the end of it — about 1.3 million electric customers, plus gas heat for roughly 130,000 more.
Nobody shops around: inside the territory Ameren is the only seller, so regulators set the price instead of the market. It has asked for $343M more a year starting mid-2027 — roughly ten percent on a home's electric bill, about $13 a month — and a Missouri legislator has asked the regulator to push back.
Large-Load Electric Service Agreements
Twelve-year contracts to sell power to big data centers: 2.8 gigawatts signed by July 2026 — more than twice Ameren's nuclear plant — led by Google and Amazon campuses in Montgomery County, Missouri. Billing starts in the second half of 2027.
Competes with Large Load Power Service tariff (Evergy) · Large-load data-center power program (Oncor) · Large-load data-center power program (Xcel Energy)
In plain English
The customers Ameren has not started billing yet. Data centers are windowless buildings packed with computers that never switch off; Missouri's new rulebook covers any of them asking for 75 megawatts or more. Sign up and you commit to twelve years, pay for at least eighty percent of the capacity you reserved whether you use it or not, and post money up front as security.
The point is that the newcomers, not the neighbours, pay for the power built for them. They buy at about 6.2 cents a kilowatt-hour, roughly half what ordinary customers pay, so Ameren's sales volume climbs much faster than its revenue does.
New Missouri Power Plants
New gas plants, batteries and solar farms adding more than four times the size of Ameren's nuclear plant by 2030 — Castle Bluff 2027, Big Hollow and Reform 2028, West Alton 2031. Nothing earns until a plant opens; the five-year building plan runs to $31.8B.
Competes with Missouri generation plan (Evergy) · Merchant gas plants (Independent power developers)
In plain English
Coal units are ageing out just as a wave of new demand signs up, so Ameren is pouring concrete: a gas plant on the site of a retired one at Castle Bluff, gas plus a big battery at Big Hollow, a much larger gas plant at West Alton, and solar farms at Vandalia, Bowling Green and Split Rail.
Almost none of this earns while the concrete is still wet. Money arrives once regulators accept a finished plant into the pile of assets Ameren is allowed to charge customers a return on. A 2025 Missouri law lets it ask to start charging earlier; it has asked for West Alton, and consumer and environmental groups are fighting that.
Ameren Illinois Electric Distribution
Wires-only delivery to 1.2 million Illinois customers — it does not own the electricity that flows through them. $2,399M of revenue and $281M of profit in FY2025; the price is fixed four years at a time, with the next plan decided in December 2026.
Competes with ComEd electric delivery (Exelon) · Retail power supply contracts (Alternative Illinois electricity suppliers)
In plain English
Think of it as the road, not the freight. Ameren Illinois owns about 46,000 miles of local power line across roughly three-quarters of the state, and every unit of electricity a household uses travels over it — but the electricity itself is bought elsewhere and passed straight through at cost.
So the bill has two parts, and only one of them is Ameren's. It earns a set amount for running and rebuilding the network, agreed with Illinois regulators four years at a time and settled up each year against what it actually spent. Growth here comes from replacing poles and adding switches, not from customers using more.
Ameren Illinois Natural Gas
Gas delivery to more than 800,000 Illinois customers, with underground storage to buy cheap in summer and deliver in winter. $968M of revenue and $158M of profit in FY2025. Winter is everything: gas was near a quarter of company revenue in early 2026 and a twentieth in the summer of 2025.
Competes with Nicor Gas distribution (Southern Company Gas) · Peoples Gas distribution (WEC Energy Group) · Electric heat pumps (Home heating equipment makers)
In plain English
A pipe under the street, a meter on the wall, and a bill that arrives mostly between November and March. Ameren Illinois delivers natural gas to more than 800,000 homes and small businesses; households are about seven of every ten dollars it collects.
It also owns underground storage fields and fills them when gas is cheap in summer, pulling it back out when the weather turns — a pantry stocked at harvest and eaten through the winter. Regulators last reset the price in November 2023. The slow threat is the electric heat pump: every house that switches is gas this business never sells again.
Ameren Transmission
The high-voltage layer above the local wires: $862M of revenue turned into $415M of profit in FY2025, nearly half of every dollar. In May 2026 a group led by Ameren won two 765,000-volt Illinois lines costing $1.66B, with Ameren holding 43%.
Competes with ITC Holdings transmission lines (Fortis) · GridLiance Heartland transmission (NextEra Energy Transmission)
In plain English
Local wires bring power down your street; this is the layer above — the tall steel towers that move electricity long distances across the region. Ameren owns a slice of that network in Illinois, and everyone whose power crosses it pays a share of the cost.
Why it matters more than its size suggests: a federal formula resets the price every year to cover what the lines actually cost plus a profit, so a dollar spent on a tower becomes earnings with little wait. A tenth of company revenue, well over a quarter of company profit. New lines, though, have to be won in contests against rival builders.
Ameren MissouriAmeren's biggest piece: it burns the fuel, spins the turbines and runs the wires to 1.3 million homes and businesses around St. Louis. $4,795M of revenue and $747M of profit in FY2025, plus $2.5B of construction — most of the company's. Watch the request to raise rates in mid-2027.Ameren's biggest piece: it burns the fuel, spins the turbines and runs the wires to 1.3 million homes and businesses around St. Louis. $4,795M of revenue and $747M of profit in FY2025, plus $2.5B of construction — most of the company's. Watch the request to raise rates in mid-2027.
In plain English
One company owns the whole chain here, from the fuel pile to the lamp on the table. Ameren Missouri runs coal, nuclear and gas plants around greater St. Louis, carries that power over its own lines, and bills the household at the end of it — about 1.3 million electric customers, plus gas heat for roughly 130,000 more.
Nobody shops around: inside the territory Ameren is the only seller, so regulators set the price instead of the market. It has asked for $343M more a year starting mid-2027 — roughly ten percent on a home's electric bill, about $13 a month — and a Missouri legislator has asked the regulator to push back.
Competes with Evergy Missouri West electricity (Evergy) · Power plants built on the customer's own site (Independent power producers)
Large-Load Electric Service AgreementsTwelve-year contracts to sell power to big data centers: 2.8 gigawatts signed by July 2026 — more than twice Ameren's nuclear plant — led by Google and Amazon campuses in Montgomery County, Missouri. Billing starts in the second half of 2027.Twelve-year contracts to sell power to big data centers: 2.8 gigawatts signed by July 2026 — more than twice Ameren's nuclear plant — led by Google and Amazon campuses in Montgomery County, Missouri. Billing starts in the second half of 2027.
In plain English
The customers Ameren has not started billing yet. Data centers are windowless buildings packed with computers that never switch off; Missouri's new rulebook covers any of them asking for 75 megawatts or more. Sign up and you commit to twelve years, pay for at least eighty percent of the capacity you reserved whether you use it or not, and post money up front as security.
The point is that the newcomers, not the neighbours, pay for the power built for them. They buy at about 6.2 cents a kilowatt-hour, roughly half what ordinary customers pay, so Ameren's sales volume climbs much faster than its revenue does.
Competes with Large Load Power Service tariff (Evergy) · Large-load data-center power program (Oncor) · Large-load data-center power program (Xcel Energy)
New Missouri Power PlantsNew gas plants, batteries and solar farms adding more than four times the size of Ameren's nuclear plant by 2030 — Castle Bluff 2027, Big Hollow and Reform 2028, West Alton 2031. Nothing earns until a plant opens; the five-year building plan runs to $31.8B.New gas plants, batteries and solar farms adding more than four times the size of Ameren's nuclear plant by 2030 — Castle Bluff 2027, Big Hollow and Reform 2028, West Alton 2031. Nothing earns until a plant opens; the five-year building plan runs to $31.8B.
In plain English
Coal units are ageing out just as a wave of new demand signs up, so Ameren is pouring concrete: a gas plant on the site of a retired one at Castle Bluff, gas plus a big battery at Big Hollow, a much larger gas plant at West Alton, and solar farms at Vandalia, Bowling Green and Split Rail.
Almost none of this earns while the concrete is still wet. Money arrives once regulators accept a finished plant into the pile of assets Ameren is allowed to charge customers a return on. A 2025 Missouri law lets it ask to start charging earlier; it has asked for West Alton, and consumer and environmental groups are fighting that.
Competes with Missouri generation plan (Evergy) · Merchant gas plants (Independent power developers)
Ameren Illinois Electric DistributionWires-only delivery to 1.2 million Illinois customers — it does not own the electricity that flows through them. $2,399M of revenue and $281M of profit in FY2025; the price is fixed four years at a time, with the next plan decided in December 2026.Wires-only delivery to 1.2 million Illinois customers — it does not own the electricity that flows through them. $2,399M of revenue and $281M of profit in FY2025; the price is fixed four years at a time, with the next plan decided in December 2026.
In plain English
Think of it as the road, not the freight. Ameren Illinois owns about 46,000 miles of local power line across roughly three-quarters of the state, and every unit of electricity a household uses travels over it — but the electricity itself is bought elsewhere and passed straight through at cost.
So the bill has two parts, and only one of them is Ameren's. It earns a set amount for running and rebuilding the network, agreed with Illinois regulators four years at a time and settled up each year against what it actually spent. Growth here comes from replacing poles and adding switches, not from customers using more.
Competes with ComEd electric delivery (Exelon) · Retail power supply contracts (Alternative Illinois electricity suppliers)
Ameren Illinois Natural GasGas delivery to more than 800,000 Illinois customers, with underground storage to buy cheap in summer and deliver in winter. $968M of revenue and $158M of profit in FY2025. Winter is everything: gas was near a quarter of company revenue in early 2026 and a twentieth in the summer of 2025.Gas delivery to more than 800,000 Illinois customers, with underground storage to buy cheap in summer and deliver in winter. $968M of revenue and $158M of profit in FY2025. Winter is everything: gas was near a quarter of company revenue in early 2026 and a twentieth in the summer of 2025.
In plain English
A pipe under the street, a meter on the wall, and a bill that arrives mostly between November and March. Ameren Illinois delivers natural gas to more than 800,000 homes and small businesses; households are about seven of every ten dollars it collects.
It also owns underground storage fields and fills them when gas is cheap in summer, pulling it back out when the weather turns — a pantry stocked at harvest and eaten through the winter. Regulators last reset the price in November 2023. The slow threat is the electric heat pump: every house that switches is gas this business never sells again.
Competes with Nicor Gas distribution (Southern Company Gas) · Peoples Gas distribution (WEC Energy Group) · Electric heat pumps (Home heating equipment makers)
Ameren TransmissionThe high-voltage layer above the local wires: $862M of revenue turned into $415M of profit in FY2025, nearly half of every dollar. In May 2026 a group led by Ameren won two 765,000-volt Illinois lines costing $1.66B, with Ameren holding 43%.The high-voltage layer above the local wires: $862M of revenue turned into $415M of profit in FY2025, nearly half of every dollar. In May 2026 a group led by Ameren won two 765,000-volt Illinois lines costing $1.66B, with Ameren holding 43%.
In plain English
Local wires bring power down your street; this is the layer above — the tall steel towers that move electricity long distances across the region. Ameren owns a slice of that network in Illinois, and everyone whose power crosses it pays a share of the cost.
Why it matters more than its size suggests: a federal formula resets the price every year to cover what the lines actually cost plus a profit, so a dollar spent on a tower becomes earnings with little wait. A tenth of company revenue, well over a quarter of company profit. New lines, though, have to be won in contests against rival builders.
Competes with ITC Holdings transmission lines (Fortis) · GridLiance Heartland transmission (NextEra Energy Transmission)
Named in filings, launches and programs
- Callaway Energy CenterProduct1,194 megawatts of nuclear power, Ameren's largest source of electricity that burns nothing; more nuclear is under study, with nothing committed.
- Labadie Energy CenterProductAt 2,372 MW, Ameren's largest coal plant; boiler work is scheduled for 2026, and burning gas alongside the coal is under study.
- Audrain Energy CenterProductBeing converted to run on two fuels, adding up to 700 MW for the coldest days, due at the end of 2026.
- Castle Bluff Energy CenterProduct · Announced800 MW gas plant rising on the site of a retired one, due in 2027 — the earliest of the new Missouri gas plants.
- Big Hollow Energy CenterProduct · Announced800 MW of gas plus a 400 MW battery, approved by Missouri regulators in February 2026, due in 2028.
- West Alton Energy CenterProduct · Announced2,100 MW gas plant filed for approval in July 2026 and targeted for 2031; its cost is undisclosed and early charging is contested.
- Reform Energy CenterProduct · Announced250 MW plant, settled with objecting parties in March 2026 and due in 2028.
- Split Rail, Huck Finn, Bowling Green and Vandalia solarProduct line · RampingSolar farms of 300, 200, 50 and 50 MW; Vandalia started up in December 2025.
- Ameren Transmission Company of IllinoisBrandAmeren's Illinois transmission arm, holding 43% of two 765,000-volt lines awarded by the regional grid operator in May 2026, with three partners.
- Ameren Illinois gas storageServiceCompany-owned underground gas fields; buying in summer and holding it for winter was worth about $63M to customers in January 2026 alone.
- Ameren Services CompanyBrandThe shared back office — support work the utilities all draw on rather than each building its own.
- Parent-level energy technology investmentsProductSmall investments outside the utilities, held at the parent company; they helped narrow the parent's loss in the second quarter of 2026.
- Energy-efficiency and customer-assistance programsCustomer programRebates, demand-shifting and bill help — more than $40M of assistance was connected to customers in the first quarter of 2026.
Callaway Energy CenterProduct
1,194 megawatts of nuclear power, Ameren's largest source of electricity that burns nothing; more nuclear is under study, with nothing committed.
Labadie Energy CenterProduct
At 2,372 MW, Ameren's largest coal plant; boiler work is scheduled for 2026, and burning gas alongside the coal is under study.
Audrain Energy CenterProduct
Being converted to run on two fuels, adding up to 700 MW for the coldest days, due at the end of 2026.
Castle Bluff Energy CenterProduct · Announced
800 MW gas plant rising on the site of a retired one, due in 2027 — the earliest of the new Missouri gas plants.
Big Hollow Energy CenterProduct · Announced
800 MW of gas plus a 400 MW battery, approved by Missouri regulators in February 2026, due in 2028.
West Alton Energy CenterProduct · Announced
2,100 MW gas plant filed for approval in July 2026 and targeted for 2031; its cost is undisclosed and early charging is contested.
Reform Energy CenterProduct · Announced
250 MW plant, settled with objecting parties in March 2026 and due in 2028.
Split Rail, Huck Finn, Bowling Green and Vandalia solarProduct line · Ramping
Solar farms of 300, 200, 50 and 50 MW; Vandalia started up in December 2025.
Ameren Transmission Company of IllinoisBrand
Ameren's Illinois transmission arm, holding 43% of two 765,000-volt lines awarded by the regional grid operator in May 2026, with three partners.
Ameren Illinois gas storageService
Company-owned underground gas fields; buying in summer and holding it for winter was worth about $63M to customers in January 2026 alone.
Ameren Services CompanyBrand
The shared back office — support work the utilities all draw on rather than each building its own.
Parent-level energy technology investmentsProduct
Small investments outside the utilities, held at the parent company; they helped narrow the parent's loss in the second quarter of 2026.
Energy-efficiency and customer-assistance programsCustomer program
Rebates, demand-shifting and bill help — more than $40M of assistance was connected to customers in the first quarter of 2026.