Ameren Illinois mailing address
To mail a letter to Ameren Illinois, an electric & natural-gas utility serving central and southern Illinois, send it to the correspondence address at Ameren Illinois, P.O. Box 88034, Chicago, IL 60680-1034. Ameren Illinois is the electric and natural-gas utility serving central and southern Illinois, a subsidiary of Ameren Corporation. This is Ameren Illinois's publicly listed correspondence address — for billing disputes, service requests, account closures, and formal notices. It's not the address utilities use for bill-payment remittance; use the PO Box printed on your own bill for payments. Add your return address if you'd like a reply, and confirm this address on Ameren Illinois's official contact page before anything time-sensitive.
Ameren Illinois — correspondence address
Ameren Illinois P.O. Box 88034 Chicago IL 60680-1034
Written correspondence — billing disputes, service requests, account closures, and formal notices. Not the separate address used for bill-payment remittance; use the payment stub or PO Box printed on your own bill for that.
Write it now. We print & mail it for $5.
Type your letter in the browser. We print it, stamp it, and hand it to USPS — usually same business day. No printer, no stamps, no post office.
$5 flat · postage included · no account needed
- You write & pay
- We print & envelope
- USPS, next business day
- Confirmation of Mailing emailed
Your name
Your return address
Ameren IllinoisP.O. Box 88034Chicago, IL 60680-1034
Your letter, printed and mailed for you.
Key facts
- This is Ameren Illinois's correspondence mailing address, taken from the utility's own contact page.
- Ameren Illinois is an electric & natural-gas utility serving central and southern Illinois.
- Use it for letters, disputes, service requests, and formal notices — not for bill payments, which go to a separate PO Box printed on your bill.
- Include your account number and service address so the utility can find your file.
- Include your return address and a reference number so the utility can respond.
- PostPal prints your letter and mails it for you — no printer, envelope, stamps, or post office trip.
How to send your letter
- 1
Decide what your letter is for
Use this address for written correspondence — a billing dispute, a service request, an account closure, or a formal notice. If you're mailing a cheque or payment, use the remittance address printed on your own bill instead; utilities almost always route payments to a separate PO Box.
- 2
Write your letter
Include your account number, your service address (if different from your mailing address), the outcome you're looking for, and your return address so Ameren Illinois can respond.
- 3
Address it to the correspondence address
First line: Ameren Illinois. Then the street: P.O. Box 88034. Then the city line: Chicago IL 60680-1034.
- 4
Send it with PostPal
Write or upload your letter to PostPal with the address above prefilled. We print it, add your return address, and mail it for you — no printer, envelope, stamps, or trip to the post office.
Common questions
What does Ameren Illinois do?
Ameren Illinois is the electric and natural-gas utility serving central and southern Illinois, a subsidiary of Ameren Corporation. It serves central and southern Illinois. The address above is its correspondence address — the right place for account letters, disputes, and formal notices.
What is Ameren Illinois's mailing address?
Ameren Illinois, P.O. Box 88034, Chicago, IL 60680-1034. This is Ameren Illinois's publicly listed correspondence address. Confirm it on Ameren Illinois's official contact page before anything time-sensitive — utilities occasionally change offices and PO Boxes.
Can I mail my bill payment to this address?
Not usually. This is a correspondence address for letters, not the payment-processing address most utilities use for mailed cheques. Use the remittance address or PO Box printed on your own bill for payments, and this address for everything else — disputes, service requests, and written notices.
How do I dispute a charge or file a complaint by mail?
Write a clear, dated letter explaining the charge or issue, include your account number and any supporting documents, state what resolution you're asking for, and include your return address. Mailing it creates a dated paper record, which can help if the dispute escalates.
How do I close or transfer my account by mail?
Include your account number, the closing/transfer date, your forwarding address, and a phone number in case Ameren Illinois needs to confirm details. Most utilities also offer this online or by phone, which is often faster if you're on a tight moving deadline — mail is best for a written record or when online/phone options aren't available.
How do I mail Ameren Illinois a letter without a printer?
Write or upload your letter to PostPal with the address prefilled. We print it, add your return address, and mail it for you — no printer, stamps, or post office trip needed.
Sources
Addresses verified September 2026 against official sources. Always confirm on the official site before time-sensitive filings.