Shareowners

We want you to have the information you need to manage your accounts, understand stock ownership acronyms and terminology, and understand the responsibilities and requirements of being a shareowner.

The guide provides definitions of common terms and explains how shareowners can transact and manage their accounts. This document is subject to change and is intended for informational purposes only. The information contained in this document is not intended to provide legal, investment, financial or other advice. For specific questions please contact your financial advisor or legal counsel.

Shareowner Education Toolkit [PDF]

There’s no wait, worry or wondering about your dividend check when you choose to have it deposited electronically into your checking or savings account.

Electronic deposits go directly into your specified account the same day dividends are paid. You’ll save time and eliminate the risk of your check being lost, stolen or misplaced.

There is no charge for electronic deposit.

How to sign up

Go to Manage Your Account on the Shareowner Online website.

You may also sign up by completing the Direct Deposit of Dividends Form [PDF] and sending it to:

EQ Shareowner Services
PO Box 64856
St Paul MN 55164-9442

EQ Shareowner Services is the transfer agent for common stock of Alliant Energy Corporation. Alliant Energy’s utility subsidiaries are Interstate Power and Light Co. (IPL) and Wisconsin Power and Light Co. (WPL).

EQ Shareowner Services handles any type of stock transfer for single or joint accounts, including:

• Name changes
• Custodial accounts
• Trusts

To transfer shares, we require:

• Stock Power Form [PDF]. The signature(s) must correspond exactly with the name(s) as it appears on the account from which it is being transferred.
• Stock Power Form instructions [PDF]
• Your signature must be witnessed by a Medallion Guarantee Program Member (contact your financial institution or broker).
• Surrender of the physical stock certificates (if any). When mailing, we suggest that you insure your package for 4% of the face value to avoid replacement costs.
• If you have questions, please contact EQ Shareowner Services at 1-800-356-5343.

Send the required documents to:

Postal mail:
EQ Shareowner Services
P.O. Box 64854
St Paul, MN 55164

Courier:
EQ Shareowner Services
1110 Centre Pointe Curve, Ste. 101
MAC N9173-010
Mendota Heights, MN 55120

With the Shareowner Direct Plan, you can purchase your shares directly. It's easy, and brokerage fees for purchases are paid by Alliant Energy.

Enroll in the Shareowner Direct Plan today on the Shareowner Online website.

The plan includes:

• $250 minimum initial purchase
• Stock certificate safekeeping
• Sale of shares
• Optional cash investments by check
• Electronic debit of checking or savings account to purchase shares
• Choice of reinvested or cash dividend

Download Investment Plan Documents and mail completed forms to:

EQ Shareowner Services
P.O. Box 64854
St. Paul, MN 55164-0856

Please mail completed forms and checks for purchases to the EQ Shareowner Services address listed above.

Direct investments are made weekly.

Dividend Reinvestment Dates:

• February 17, 2026
• May 15, 2026
• August 17, 2026
• November 16, 2026

Individual taxpayers are responsible for tracking the cost basis of their noncovered investments.

You can request your cost basis information for shares purchased on or after January 1, 2011 from EQ Shareowner Services Customer Care. Call 1-800-356-5343 or log into your account on the Shareowner Online website.

Enroll in Shareowner Online

Stock acquired prior to January 1, 2011 is considered noncovered and does not require cost basis reporting. However, you can obtain the average trade price of your stock (high and low price on date of purchase) on MarketWatch. Data goes back to January 1989.

NetBasis Individual Investors has a service that you can use to obtain your cost basis information. You will need to provide the following to obtain the report: Dates and number of shares purchased, acquired, or inherited, along with any dates and quantities of shares sold.

Important information about protecting your Alliant Energy Corporation stock from escheatment:

"Escheating" is reporting and transferring shares to a state unclaimed property division. Alliant Energy Corporation is required to escheat your shares in Alliant Energy Corporation and/or uncashed dividend checks if they are considered abandoned property under relevant state law. Several factors might cause your shares and/or dividend checks to be considered abandoned property:

• Returned mail.
• Lack of contact with our transfer agent (EQ Shareowner Services) on an annual basis.
• Uncashed checks.

Once your shares and/or dividend funds have been escheated, you will need to file a claim with the relevant state for the return of your property.

What can you do to help prevent the escheatment of your shares/dividends? Maintain activity on your account via annual communication with EQ Shareowner Services. This can be done by phone, mail, email, or by logging into your shareowner account on their website at shareowneronline.com to verify your account information. In some states, voting your proxy also counts as contact for unclaimed property purposes. Please be sure to keep your address up to date and promptly cash all dividend and sale proceeds checks.

Did you receive a letter from EQ Unify? The letter is legitimate. It is legally-required due diligence to contact shareowner accounts with no shareowner-initiated activity for at least three years. Dividend reinvestment or ACH deposit of cash dividends is not considered shareowner-initiated activity.

To keep your account active, please call EQ Shareowner Services Customer Care at 1-800-356-5343 immediately. Provide your account number and let the representative know you are calling to make contact and keep your account active.

Moving forward, you will need to make contact annually to keep your account active. Other forms of shareowner-initiated activity include:

• An additional voluntary cash contribution.
• Submitting an account authorization form to make updates to your account. Updates can include banking information, automatic investments, changing dividend reinvestment election, updating your address, or signing into your account online.