Obbligazione Interstate Energy & Lighting 3.4% ( US461070AM60 ) in USD

Interstate Energy & Lighting

100 USD ▼

Stati Uniti

US461070AM60 ( in USD )

3.4% per anno ( pagato 2 volte l'anno)

15/08/2025

Prospetto opuscolo dell'obbligazione Interstate Power and Light US461070AM60 en USD 3.4%, scadenza 15/08/2025

1 000 USD

250 000 000 USD

461070AM6

A- ( Upper medium grade - Investment-grade )

Baa1 ( Lower medium grade - Investment-grade )

15/08/2025 ( In 7 giorni )

Interstate Power and Light era una società di servizi pubblici statunitense, con sede a Kansas City, Missouri, che operava principalmente nell'Iowa e nel Missouri, fornendo energia elettrica e gas naturale.

The Obbligazione issued by Interstate Energy & Lighting ( United States ) , in USD, with the ISIN code US461070AM60, pays a coupon of 3.4% per year.
The coupons are paid 2 times per year and the Obbligazione maturity is 15/08/2025

The Obbligazione issued by Interstate Energy & Lighting ( United States ) , in USD, with the ISIN code US461070AM60, was rated Baa1 ( Lower medium grade - Investment-grade ) by Moody's credit rating agency.

The Obbligazione issued by Interstate Energy & Lighting ( United States ) , in USD, with the ISIN code US461070AM60, was rated A- ( Upper medium grade - Investment-grade ) by Standard & Poor's ( S&P ) credit rating agency.

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Table of Contents
Filed Pursuant to Rule 424(b)(5)
Registration No. 333-200941-01
CALCULATION OF REGISTRATION FEE

Maximum
Title of each class of
aggregate
Amount of
securities to be registered

offering price
registration fee (1)
3.400% Senior Debentures due 2025

$249,350,000

$17,354.47 (2)

(1)
The filing fee is calculated in accordance with Rule 457(r) under the Securities Act of 1933.
(2)
Pursuant to Rule 415(a)(6) under the Securities Act of 1933, $100,000,000 in aggregate offering price of Interstate Power and Light
Company's unsold debt securities were carried forward on registration statement No. 333-200941-01 filed by the registrant on December 15,
2014, for which $11,460 in registration fees were previously paid and are being applied to $100,000,000 in aggregate offering price of the
Senior Debentures. The registration fee listed above relates to the remaining part of the aggregate offering price of the Senior Debentures.
Table of Contents

Prospectus Supplement
(To Prospectus dated December 15, 2014)
$250,000,000
Interstate Power and Light Company
3.400% Senior Debentures due 2025

We will pay interest on the senior debentures semi-annually in arrears on February 15 and August 15 of each year, beginning on February 15,
2016. The senior debentures will mature on August 15, 2025. We may redeem some or all of the senior debentures at any time and from time to
time at the applicable redemption price described in this prospectus supplement.
The senior debentures will be our unsecured senior obligations and rank equally with our other unsecured senior indebtedness from time to
time outstanding. The senior debentures will be issued only in registered form in minimum denominations of $1,000 and integral multiples of
$1,000 in excess thereof. The senior debentures are a new issue of securities with no established trading market. We currently have no intention to
apply to list the senior debentures on any securities exchange or to seek their admission to trading on any automated quotation system.

Investing in the senior debentures involves risks. See "Risk Factors" beginning on page 22 of our Annual
Report on Form 10-K for the year ended December 31, 2014, as such discussion may be amended or updated in
other reports filed by us with the Securities and Exchange Commission. These Risk Factors, as amended or
updated, are incorporated by reference herein.

Per

Debenture

Total

Public offering price(1)

99.740%
$249,350,000
Underwriting discount

0.65%
$
1,625,000
Proceeds, before expenses, to Interstate Power and Light Company(1)

99.090%
$247,725,000

(1)
Plus accrued interest, if any, from August 18, 2015, if settlement occurs after that date.
Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or
determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal
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offense.
The debentures will be available for delivery in book-entry form only through The Depository Trust Company on or about August 18, 2015.

Joint Book-Running Managers

MUFG

Mizuho Securities

Wells Fargo Securities

Co-Managers

Barclays

KeyBanc Capital Markets

The Williams Capital Group, L.P.

The date of this prospectus supplement is August 13, 2015.
Table of Contents
TABLE OF CONTENTS

Prospectus Supplement

Page
About this Prospectus Supplement

ii
Forward-Looking Statements

iii
Prospectus Supplement Summary
S-1
Use of Proceeds
S-6
Capitalization
S-7
The Company
S-8
Description of Senior Debentures
S-9
Underwriting
S-14
Legal Matters
S-17
Experts
S-17
Prospectus

Page
About this Prospectus

1
Forward-Looking Statements

2
Interstate Power and Light Company

3
Risk Factors

4
Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements

5
Use of Proceeds

5
Description of Preferred Stock

6
Description of Debt Securities

8
Plan of Distribution

16
Where You Can Find More Information

18
Legal Matters

19
Experts

19

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Table of Contents
ABOUT THIS PROSPECTUS SUPPLEMENT
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This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering. The second
part, the accompanying prospectus, gives more general information, some of which may not apply to this offering. You should read the entire
prospectus supplement, as well as the accompanying prospectus and the documents incorporated by reference that are described under "Where You
Can Find More Information" in the accompanying prospectus. Some of these documents, however, are filed on a combined basis with our parent,
Alliant Energy Corporation, and its direct subsidiary, Wisconsin Power and Light Company. Information contained in these documents relating to
those entities is filed by them on their own behalf and not by us and is not incorporated by reference in this prospectus supplement or the
accompanying prospectus. The senior debentures are not obligations of, or guaranteed by, Alliant Energy Corporation or Wisconsin Power and
Light Company and you should not rely on that information when deciding whether to invest in our senior debentures. In the event that the
description of the offering varies between this prospectus supplement and the accompanying prospectus, you should rely on the information
contained in this prospectus supplement.
You should rely only on the information relating solely to Interstate Power and Light Company contained or incorporated by reference in this
prospectus supplement, the accompanying prospectus and any related free writing prospectus prepared by or on behalf of us or to which we have
referred you. We have not, and the underwriters have not, authorized any other person to provide you with different information. If anyone
provides you with different or inconsistent information, you should not rely on it. We are not, and the underwriters are not, making an offer to sell
these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus
supplement, the accompanying prospectus and the documents incorporated by reference is accurate only as of the respective dates of those
documents in which the information is contained. Our business, financial condition, results of operations and prospects may have changed since
any such date.
Unless we otherwise indicate or unless the context requires otherwise, all references in this prospectus supplement to "we," "our," "us" or
similar references mean Interstate Power and Light Company.
Our principal executive offices are located at Alliant Energy Tower, 200 First Street, SE, Cedar Rapids, Iowa 52401, and our telephone
number is (319) 786-4411.

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Table of Contents
FORWARD-LOOKING STATEMENTS
This prospectus supplement, the accompanying prospectus and the information incorporated by reference herein or therein contain forward-
looking statements intended to qualify for the safe harbors from liability established by the Private Securities Litigation Reform Act of 1995. All
statements, other than statements of historical fact, included in this prospectus supplement, the accompanying prospectus or incorporated by
reference herein or therein, including statements regarding anticipated financial performance, business strategy and management's plans and
objectives for future operations, are forward-looking statements. These forward-looking statements can be identified as such because the
statements generally include words such as "may," "believe," "expect," "anticipate," "plan," "project," "will," "projections," "estimate," or other
similar expressions. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ
materially from those expressed in, or implied by, these statements. Readers are cautioned not to place undue reliance on these forward-looking
statements. All forward-looking statements included in this prospectus supplement, the accompanying prospectus or in any document incorporated
by reference herein or therein speak only as of the date of this prospectus supplement, the accompanying prospectus or the document incorporated
by reference, as the case may be. Additional information concerning factors that could cause actual results to differ materially from those in the
forward-looking statements is contained under "Risk Factors" on page 4 of the accompanying prospectus and in other documents that we file from
time to time with the U.S. Securities and Exchange Commission ("SEC") that are incorporated by reference into this prospectus supplement and
the accompanying prospectus, including, but not limited to, the risk factor disclosure beginning on page 22 of our Annual Report on Form 10-K for
the fiscal year ended December 31, 2014. Some, but not all, of the risks and uncertainties that could materially affect actual results include the
following:

·
federal and state regulatory or governmental actions, including the impact of energy, tax, financial and health care legislation, and

regulatory agency orders;

·
our ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of fuel costs, operating costs,

transmission costs, deferred expenditures, capital expenditures, and remaining costs related to electric generating units ("EGUs") that
may be permanently closed, earning our authorized rates of return, and the payments to our parent of expected levels of dividends;

·
the ability to continue cost controls and operational efficiencies;

·
the impact of our retail electric base rate freeze in Iowa during 2015 and 2016;

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·
weather effects on results of utility operations, including impacts of temperature changes in our service territory on customers' demand

for electricity and gas;

·
the impact of the economy in our service territory and the resulting impacts on sales volumes, margins and the ability to collect unpaid

bills;

·
the impact of customer- and third party-owned generation, including alternative electric suppliers, in our service territory on system

reliability, operating expenses and customers' demand for electricity;

·
the impact of energy efficiency, franchise retention, customer- and third party-owned generation and customer disconnects on sales

volumes and margins;

·
the impact that price changes may have on our customers' demand for electric, gas and steam services, and their ability to pay their

bills;

·
developments that adversely impact our ability to implement our strategic plan, including unanticipated issues with new emission

controls equipment for our various coal-fired EGUs, construction of the Marshalltown Generating Station, various replacements and
expansion of our natural gas distribution systems, and the potential decommissioning of certain of our EGUs;

·
issues related to the availability and operations of EGUs, including start-up risks, breakdown or failure of equipment, performance

below expected or contracted levels of output or efficiency, operator error, transmission constraints, compliance with mandatory
reliability standards and risks related to recovery of resulting incremental costs through rates;

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Table of Contents

·
disruptions in the supply and delivery of coal, natural gas and purchased electricity;

·
changes in the price of delivered coal, natural gas and purchased electricity due to shifts in supply and demand caused by market

conditions and regulations, and the ability to recover and to retain the recovery of related changes in purchased power, fuel and fuel-
related costs through rates in a timely manner;

·
issues associated with environmental remediation and environmental compliance, including compliance with the Consent Decree
between us, the United States of America Environmental Protection Agency (the "EPA"), the Sierra Club, the State of Iowa and Linn

County in Iowa, the Coal Combustion Residuals Rule, future changes in environmental laws and regulations, including the EPA's
regulations for carbon dioxide emissions reductions from new and existing fossil-fueled EGUs, and litigation associated with
environmental requirements;

·
the ability to defend against environmental claims brought by state and federal agencies, such as the EPA, state natural resources

agencies or third parties, such as the Sierra Club, and the impact on operating expenses of defending and resolving such claims;

·
the ability to recover through rates all environmental compliance and remediation costs, including costs for projects put on hold due to

uncertainty of future environmental laws and regulations;

·
impacts that storms or natural disasters in our service territory may have on our operations and recovery of, and rate relief for, costs

associated with restoration activities;

·
the direct or indirect effects resulting from terrorist incidents, including physical attacks and cyber attacks, or responses to such

incidents;

·
the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable

information, including associated costs to notify affected persons and to mitigate their information security concerns;

·
the direct or indirect effects resulting from breakdown or failure of equipment in the operation of natural gas distribution systems, such

as leaks, explosions and mechanical problems, and compliance with natural gas distribution safety regulations, such as those that may
be issued by the Pipeline and Hazardous Materials Safety Administration;

·
risks associated with implementing a new customer billing and information system currently expected by the end of the first quarter of

2016;

·
impacts of future tax benefits from Iowa rate-making practices, including deductions for repairs expenditures and allocation of mixed

service costs, and recoverability of the associated regulatory assets from customers, when the differences reverse in future periods;

·
any material post-closing adjustments related to any past asset divestitures, including the sales of our Minnesota electric and natural gas
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distribution assets, which could result from, among other things, warranties, parental guarantees or litigation;

·
continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;

·
inflation and interest rates;

·
changes to the creditworthiness of counterparties with which we have contractual arrangements, including participants in the energy

markets and fuel suppliers and transporters;

·
issues related to electric transmission, including operating in Regional Transmission Organization energy and ancillary services

markets, the impacts of potential future billing adjustments and cost allocation changes from Regional Transmission Organizations and
recovery of costs incurred;

·
current or future litigation, regulatory investigations, proceedings or inquiries, including the flood damage lawsuit pending against

Cedar Rapids and Iowa City Railway Company;

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Table of Contents
·
employee workforce factors, including changes in key executives, collective bargaining agreements and negotiations, work stoppages or

restructurings;

·
access to technological developments;

·
adverse developments in the food manufacturing industry, including animal flu and other illnesses;

·
changes in technology that alter the channels through which electric customers buy or utilize power;

·
material changes in retirement and benefit plan costs;

·
the impact of performance-based compensation plans accruals;

·
the effect of accounting pronouncements issued periodically by standard-setting bodies, including a new revenue recognition standard,

which is currently expected to be adopted in 2018;

·
the impact of changes to production tax credits for wind projects;

·
the impact of adjustments made to deferred tax assets and liabilities from state apportionment assumptions;

·
the ability to utilize tax credits and net operating losses generated to date, and those that may be generated in the future, before they

expire;

·
the ability to successfully complete tax audits and changes in tax accounting methods, including changes required by new tangible

property regulations with no material impact on earnings and cash flows; and

·
factors listed in Management's Discussion and Analysis of Financial Condition and Results of Operations in the combined Quarterly

Report on Form 10-Q and Annual Report on Form 10-K filed by Alliant Energy Corporation, Wisconsin Power and Light Company
and us for the quarter ended June 30, 2015 and the year ended December 31, 2014, respectively.
We assume no obligation, and disclaim any duty, to update the forward-looking statements in this prospectus, except as required by law.

-v-
Table of Contents
PROSPECTUS SUPPLEMENT SUMMARY
This summary highlights information contained elsewhere in this prospectus supplement and the accompanying prospectus. This
summary may not contain all of the information that may be important to you. You should read this entire prospectus supplement and the
accompanying prospectus carefully before making a decision to invest in our senior debentures.
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Our Company
We are a public utility serving customers in Iowa. We are engaged principally in:

·
the generation and distribution of electricity in select markets in Iowa;

·
the distribution and transportation of natural gas in select markets in Iowa;

·
the delivery of electricity to wholesale customers in select markets in the Midwest; and

·
the generation and distribution of steam for two customers in Cedar Rapids, Iowa, and various other energy-related products and

services.
As of December 31, 2014, we served 529,192 retail electric customers in 752 communities and 235,014 retail gas customers in 243
communities. As of December 31, 2014, Minnesota retail electric and gas customers were 42,338 and 10,712, respectively.
All of our common stock is owned by Alliant Energy Corporation, a regulated investor-owned public utility holding company with
subsidiaries, including us, serving primarily electricity and natural gas customers in the Midwest.
In April 2015, we completed the sale of our Minnesota natural gas distribution assets and received proceeds of $11 million and a
promissory note of $2 million. In July 2015, we completed the sale of our Minnesota electric distribution assets and received proceeds of $127
million, which were used to reduce cash proceeds received from our sales of accounts receivable program. Final proceeds are subject to post-
closing adjustments based on the value of the net assets as of the closing date and are expected to be approximately $130 million. The
premium received over the book value of the property, plant and equipment sold was more than offset by tax-related regulatory assets
associated with the distribution assets, resulting in pre-tax charges of $12 million. In July 2015, the Federal Energy Regulatory Commission, or
FERC, approved the wholesale power supply agreement between us and Southern Minnesota Energy Cooperative, which became effective
upon the sale of our Minnesota electric distribution assets.
We are subject to the jurisdiction of the Iowa Utilities Board, or IUB. We are also subject to the jurisdiction of FERC. Our parent
corporation, Alliant Energy Corporation, is a "holding company" and we are a "subsidiary company" within the Alliant Energy Corporation
"holding company system" as defined under the Public Utility Holding Company Act of 2005. As a result, we are subject to some of the
regulatory provisions of that Act.

S-1
Table of Contents
The Offering
The following is a brief summary of some of the terms of this offering. For a more complete description of the terms of the senior
debentures, see "Description of Senior Debentures" in this prospectus supplement and "Description of Debt Securities" in the accompanying
prospectus.

Issuer
Interstate Power and Light Company

Senior debentures offered
$250 million aggregate principal amount of 3.400% senior debentures due 2025.

Maturity
August 15, 2025.

Interest payment dates
February 15 and August 15 of each year, beginning on February 15, 2016.

Ranking
The senior debentures will be our unsecured senior obligations and rank equally with
our other unsecured senior indebtedness from time to time outstanding. The senior
debentures will also be subordinated to any secured indebtedness to the extent of the
assets securing such indebtedness. We do not currently have any secured indebtedness.

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Optional redemption
The senior debentures will be redeemable, at our option, in whole or in part at any time
or from time to time prior to May 15, 2025, at the applicable redemption price described
in "Description of Senior Debentures--Optional Redemption" plus accrued and unpaid
interest, if any, to, but excluding, the redemption date. We may also redeem all or a
portion of the senior debentures at our option at any time on or after May 15, 2025, at a
redemption price equal to 100% of the principal amount of the senior debentures to be
redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption
date.

Covenants
The indenture governing the senior debentures contains covenants that, among other
things, limit our ability to:

· create certain types of secured indebtedness without providing for the senior

debentures to be equally and ratably secured; and

· consolidate, merge or sell assets.

These covenants are subject to important exceptions and qualifications, which are
described under the heading "Description of Debt Securities" in the accompanying
prospectus.

No limitation on debt
The indenture governing the senior debentures does not limit the amount of senior
unsecured debt securities that we may issue or provide holders any protections should
we be involved in a highly leveraged transaction.

Use of proceeds
We estimate that we will receive net proceeds from this offering of approximately
$247.2 million, after deducting the underwriting discount and estimated offering
expenses payable by us. We intend to use the net proceeds from this offering to reduce
commercial paper

S-2
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classified as long-term debt, reduce outstanding capital under our receivables purchase

and sale program and/or for general corporate purposes.

Denominations
The senior debentures will be issued in minimum denominations of $1,000 and integral
multiples of $1,000 in excess thereof.

Absence of market for the senior debentures
The senior debentures are a new issue of securities with no established trading market.
We currently have no intention to apply to list the senior debentures on any securities
exchange or to seek their admission to trading on any automated quotation system.
Accordingly, we cannot provide any assurance as to the development or liquidity of any
market for the senior debentures. See "Underwriting." Furthermore, the market price for
the senior debentures may be adversely impacted by fluctuations in interest rates.

S-3
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Summary Consolidated Financial Information
The summary consolidated financial information below was selected or derived from our consolidated financial statements. The
unaudited interim period financial information, in our opinion, includes all adjustments, which are normal and recurring in nature, necessary
for a fair presentation for the periods shown. Results for the six months ended June 30, 2015 are not necessarily indicative of results to be
expected for the full fiscal year. The information set forth below is qualified in its entirety by and should be read in conjunction with our
Management's Discussion and Analysis of Financial Condition and Results of Operations and our consolidated financial statements and
related notes incorporated by reference into this prospectus supplement and the accompanying prospectus. See "Where You Can Find More
Information."

Six Months Ended

Year Ended December 31,

June 30,

2012

2013

2014

2014
2015

(In millions)

Income Statement Data:

Operating revenues

$1,650.3
$1,818.8
$1,848.1
$940.8
$871.2
Operating income

200.3

212.0

209.2
91.5
99.3
Net income

150.2

189.9

194.6
66.9
69.6
Earnings available for common stock

137.6

173.6

184.4
61.8
64.5

As of December 31,

As of June 30,

2013

2014

2015

(In millions)

Balance Sheet Data:

Current assets

$ 535.9
$ 556.1
$
542.9
Property, plant and equipment, net

4,136.8
4,554.7

4,687.8
Investments and other non-current assets

1,133.3
1,351.0

1,357.2
Current liabilities

524.3

705.9

543.2
Long-term debt, net (excluding current portion)

1,520.0
1,618.7

1,730.2
Other non-current liabilities

1,882.0
2,123.1

2,205.8

S-4
Table of Contents
Ratios of Earnings to Fixed Charges
The following table sets forth our ratio of earnings to fixed charges for the periods presented:

Year Ended December 31,

Six Months Ended June 30,
2010

2011

2012

2013

2014

2014
2015
3.23x

2.70x

2.64x

2.85x

2.57x

2.28x

2.30x

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USE OF PROCEEDS
We estimate that we will receive net proceeds from this offering of approximately $247.2 million, after deducting the underwriting discount
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and estimated offering expenses payable by us. We intend to use the net proceeds from this offering to reduce commercial paper classified as long-
term debt, reduce outstanding capital under our receivables purchase and sale program and/or for general corporate purposes. As of June 30, 2015,
our $111.2 million of outstanding commercial paper classified as long-term debt had a weighted average interest rate of 0.5% and a weighted
average remaining maturity of six days. As of June 30, 2015, our receivables purchase and sale program had an outstanding balance of
$100.0 million and an annualized commercial paper yield rate of 0.21%. Pending application of the net proceeds from this offering, we intend to
place the proceeds in short-term instruments.

S-6
Table of Contents
CAPITALIZATION
The following table sets forth our consolidated capitalization as of June 30, 2015 on an actual basis and as adjusted to give effect to this
offering, the anticipated use of the net proceeds from this offering as described under "Use of Proceeds."

As of June 30, 2015

% of Total

Actual
As Adjusted
as Adjusted

(In millions)

Common equity:

Common stock

$
33.4
$
33.4

0.8%
Additional paid-in capital

1,342.8

1,342.8

33.8
Retained earnings

532.5

532.5

13.4

Total common equity

1,908.7

1,908.7

48.0
Cumulative preferred stock

200.0

200.0

5.0
Long-term debt, net

Existing long-term debt

1,730.2

1,619.0

40.7
Senior debentures offered hereby

--

250.0

6.3

Total long-term debt, net

1,730.2

1,869.0

47.0

Total capitalization

$3,838.9
$
3,977.7

100.0%

S-7
Table of Contents
THE COMPANY
We are a public utility serving customers in Iowa. We are engaged principally in:

·
the generation and distribution of electricity in select markets in Iowa;

·
the distribution and transportation of natural gas in select markets in Iowa;

·
the delivery of electricity to wholesale customers in select markets in the Midwest; and

·
the generation and distribution of steam for two customers in Cedar Rapids, Iowa and various other energy-related products and

services.
As of December 31, 2014, we served 529,192 retail electric customers in 752 communities and 235,014 retail gas customers in 243
communities. As of December 31, 2014, Minnesota retail electric and gas customers were 42,338 and 10,712, respectively.
All of our common stock is owned by Alliant Energy Corporation, a regulated investor-owned public utility holding company with
subsidiaries, including us, serving primarily electricity and natural gas customers in the Midwest.
In April 2015, we completed the sale of our Minnesota natural gas distribution assets and received proceeds of $11 million and a promissory
note of $2 million. In July 2015, we completed the sale of our Minnesota electric distribution assets and received proceeds of $127 million, which
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were used to reduce cash proceeds received from our sales of accounts receivable program. Final proceeds are subject to post-closing adjustments
based on the value of the net assets as of the closing date and are expected to be approximately $130 million. The premium received over the book
value of the property, plant and equipment sold was more than offset by tax-related regulatory assets associated with the distribution assets,
resulting in pre-tax charges of $12 million. In July 2015, FERC approved the wholesale power supply agreement between us and Southern
Minnesota Energy Cooperative, which became effective upon the sale of our Minnesota electric distribution assets.

S-8
Table of Contents
DESCRIPTION OF SENIOR DEBENTURES
We have summarized provisions of the senior debentures below. This summary supplements and, to the extent inconsistent with, replaces the
description of the general terms and provisions of the debt securities under the caption "Description of Debt Securities" in the accompanying
prospectus. We will issue the senior debentures as a separate series of securities under an indenture, dated as of August 20, 2003, between us and
The Bank of New York Mellon Trust Company, N.A., as successor trustee. The indenture is described in the accompanying prospectus.
General
The indenture does not limit the aggregate principal amount of senior unsecured debt securities that we may issue under it, and provides that
we may issue, without the consent of holders of the senior debentures, securities under the indenture from time to time in one or more series
pursuant to the terms of one or more supplemental indentures, board resolutions or officer's certificates creating the series. The indenture does not
give holders of the senior debentures protection in the event we engage in a highly leveraged or other transaction that may adversely affect holders
of the senior debentures. As of the date of this prospectus supplement, we have $250.0 million aggregate principal amount of 7.25% senior
debentures due 2018, $100.0 million aggregate principal amount of 5.875% senior debentures due 2018, $200.0 million aggregate principal amount
of 3.65% senior debentures due 2020, $250.0 million aggregate principal amount of 3.25% senior debentures due 2024, $50.0 million aggregate
principal amount of 5.50% senior debentures due 2025, $100.0 million aggregate principal amount of 6.45% senior debentures due 2033,
$125.0 million aggregate principal amount of 6.30% senior debentures due 2034, $300.0 million aggregate principal amount of 6.25% senior
debentures due 2039 and $250.0 million aggregate principal amount of 4.70% senior debentures due 2043 outstanding under the indenture.
We are initially offering the senior debentures in the aggregate principal amount of $250 million. We may, without the consent of the holders
of the senior debentures, issue additional senior debentures in the future having the same ranking, interest rate, maturity and other terms, except for
the public offering price, issue date and, if applicable, the initial interest payment date as the senior debentures we offer by this prospectus
supplement. Any such additional senior debentures having such similar terms, together with the senior debentures, may constitute a single series of
senior debentures under the indenture.
No sinking fund will be established for the benefit of the senior debentures.
Maturity and Interest
The senior debentures will mature on August 15, 2025. Each senior debenture will bear interest from August 18, 2015, or from and including
the most recent interest payment date to which we have paid interest, at the rate of 3.400% per year. We will pay interest semi-annually in arrears,
on February 15 and August 15, commencing February 15, 2016, to the persons in whose names the senior debentures are registered at the close of
business on the fifteenth calendar day (whether or not a business day) before each interest payment date. Interest will be computed on the basis of a
360-day year comprised of twelve 30-day months. In the event that any interest payment date does not fall on a business day, interest on the senior
debentures will be paid on the immediately succeeding business day, without any additional interest paid as a result of such delay.
Ranking
The senior debentures will be our senior, unsecured and unsubordinated obligations, ranking equally and ratably with all our other senior,
unsecured and unsubordinated obligations from time to time outstanding. The senior debentures will be effectively subordinated to all of our
secured indebtedness to the extent of the assets securing such indebtedness. We do not currently have any secured indebtedness.

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