Obligation Interstate Energy & Lighting 4.7% ( US461070AK05 ) en USD

Interstate Energy & Lighting

87.17 % ▼

Etas-Unis

US461070AK05 ( en USD )

4.7% par an ( paiement semestriel )

15/10/2043

Prospectus brochure de l'obligation Interstate Power and Light US461070AK05 en USD 4.7%, échéance 15/10/2043

1 000 USD

250 000 000 USD

461070AK0

BBB+ ( Qualité moyenne inférieure )

Baa1 ( Qualité moyenne inférieure )

15/04/2026 ( Dans 67 jours )

Interstate Power and Light (IPL) était une entreprise d'électricité américaine, rachetée par Alliant Energy en 2000.

L'Obligation émise par Interstate Energy & Lighting ( Etas-Unis ) , en USD, avec le code ISIN US461070AK05, paye un coupon de 4.7% par an.
Le paiement des coupons est semestriel et la maturité de l'Obligation est le 15/10/2043

L'Obligation émise par Interstate Energy & Lighting ( Etas-Unis ) , en USD, avec le code ISIN US461070AK05, a été notée Baa1 ( Qualité moyenne inférieure ) par l'agence de notation Moody's.

L'Obligation émise par Interstate Energy & Lighting ( Etas-Unis ) , en USD, avec le code ISIN US461070AK05, a été notée BBB+ ( Qualité moyenne inférieure ) par l'agence de notation Standard & Poor's ( S&P ).

Final Prospectus Supplement
http://www.sec.gov/Archives/edgar/data/52485/000119312513391547/d...
424B5 1 d605988d424b5.htm FINAL PROSPECTUS SUPPLEMENT
Table of Contents
Filed Pursuant to Rule 424(b)(5)
Registration No. 333-178577-02
Prospectus Supplement
(To Prospectus dated December 16, 2011)
$250,000,000
4.70% Senior Debentures due 2043
We will pay interest on the senior debentures on April 15 and October 15 of each year, beginning on April 15, 2014. The senior
debentures will mature on October 15, 2043. We may redeem some or all of the senior debentures at any time and from time to time at
the redemption prices 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, and will not be listed on any securities exchange.
Investing in the senior debentures involves risks. See "Risk Factors" beginning on page 20 of our Annual Report on Form
10-K for the year ended December 31, 2012.

Per Senior

Debenture

Total

Public offering price(1)

99.378%
$248,445,000
Underwriting discount

0.875%

$ 2,187,500
Proceeds, before expenses, to Interstate Power and Light Company(1)

98.503%
$246,257,500
(1) Plus accrued interest if any, from October 8, 2013, 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 offense.
The senior debentures will be available for delivery in book-entry form only through The Depository Trust Company on or
about October 8, 2013.

Joint Book-Running Managers

Goldman, Sachs & Co.

Mitsubishi UFJ Securities

RBS

Co-Managers

BNY Mellon Capital Markets, LLC

Mizuho Securities

The Williams Capital Group, L.P.

The date of this prospectus supplement is October 3, 2013.

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TABLE OF CONTENTS
Prospectus Supplement

Page
About this Prospectus Supplement
ii

Forward-Looking Statements
iii

Prospectus Supplement Summary
S-1

Use of Proceeds
S-5

Capitalization
S-5

The Company
S-6

Description of Senior Debentures
S-7

Material United States Federal Income Tax Considerations
S-11
Underwriting
S-15
Legal Matters
S-19
Experts
S-19
Prospectus

Page
About this Prospectus

1

Forward-Looking Statements

1

Interstate Power and Light Company

2

Risk Factors

2

Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements
3

Use of Proceeds

3

Description of Preferred Stock

3

Description of Debt Securities

5

Plan of Distribution

13
Where You Can Find More Information

15
Legal Matters

16
Experts

16

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ABOUT THIS PROSPECTUS SUPPLEMENT
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 and the accompanying prospectus. 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 those dates.
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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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 "expect," "intend,"
"believe," "anticipate," "estimate," "plan" or "objective" 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 2 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 20
of our Annual Report on Form 10-K for the fiscal year ended December 31, 2012. 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 of regulatory agency orders;

·
our ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of operating costs, fuel
costs, transmission costs, deferred expenditures, capital expenditures, and remaining costs related to generating units 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;

·
weather effects on results of utility operations, including the impacts of temperature changes and drought conditions in our

service territories on customers' demand for electricity and gas;

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

collect unpaid bills;

·
the impact of energy efficiency, franchise retention, and customer-owned generation on sales, volumes, and margins;

·
developments that adversely impact our ability to implement our strategic plan, including unanticipated issues with new
emission controls equipment for various of our coal-fired electric generating facilities, construction of our proposed

natural gas-fired electric generating facility in Iowa, our recently approved purchased power agreement with NextEra
Energy Resources, LLC, the potential decommissioning of certain of our generating facilities, and the sale of our
distribution assets in Minnesota;

·
issues related to the availability of generating facilities and the supply and delivery of fuel and purchased electricity and

the price thereof, including the ability to recover and to retain the recovery of purchased power, fuel and fuel-related costs
through rates in a timely manner;

·
the impact that fuel and fuel-related prices may have on our customers' demand for utility services;

·
issues associated with environmental remediation and environmental compliance, further changes in environmental laws

and regulations, and litigation associated with environmental requirements;

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·
the ability to defend against environmental claims brought by state and federal agencies, such as the United States of

America Environmental Protection Agency, or third parties, such as the Sierra Club;

·
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;

·
the direct or indirect effects resulting from terrorist incidents, including cyber terrorism, 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;

·
impacts of future tax benefits from deductions for repairs expenditures and mixed service costs and temporary differences

from historical tax benefits from such deductions that are included in rates when the differences reverse in future periods;

·
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 Organizations ("RTOs") energy and

ancillary services markets, the impacts of potential future billing adjustments and cost allocation changes from RTOs and
recovery of costs incurred;

·
unplanned outages, transmission constraints or operational issues impacting fossil or renewable generating facilities and

risks related to recovery of resulting incremental costs through rates;

·
Alliant Energy Corporation's ability to successfully pursue appropriate appeals with respect to, and any liabilities arising

out of, the alleged violation of the Employee Retirement Income Security Act of 1974 by the Alliant Energy Cash Balance
Pension Plan;

·
current or future litigation, regulatory investigations, proceedings or inquiries;

·
employee workforce factors, including changes in key executives, collective bargaining agreements and negotiations, work

stoppages or additional restructurings;

·
impacts that storms or natural disasters, including floods, droughts, and forest or prairie fires, in our service territories

may have on their operations and recovery of, and rate relief for, costs associated with restoration activities;

·
the impact of distributed generation, including alternative electric suppliers, in our service territories on system reliability,

operating expenses and customer's demand for electricity;

·
access to technological developments;

·
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;

·
the impact of changes to government incentives 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;

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·
the ability to successfully complete tax audits, changes in tax accounting methods and appeals with no material impact on

earnings and cash flows; and

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

combined Annual Report on Form 10-K filed by Alliant Energy Corporation, Wisconsin Power and Light Company and us
for the year ended December 31, 2012.
We assume no obligation, and disclaim any duty, to update or revise publicly any forward-looking statements, whether as a
result of new information, future events or otherwise.

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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.
Our Company
We are a public utility serving customers in Iowa and southern Minnesota. We are engaged principally in:

· the generation and distribution of electricity in selective markets in Iowa and southern Minnesota;

· the distribution and transportation of natural gas in selective markets in Iowa and southern Minnesota; 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, 2012, we served 526,841 retail electric customers in 752 communities and 233,820 retail gas
customers in 243 communities.
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.
We are subject to the jurisdiction of the Iowa Utilities Board, or IUB, and the Minnesota Public Utilities Commission, or
MPUC, with respect to various portions of our operations. We are also subject to the jurisdiction of the Federal Energy
Regulatory Commission, or 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.
Recent Developments
On September 3, 2013, we announced agreements to sell our Minnesota electric and natural gas distribution businesses. The
electric distribution business in the state is expected to be sold to Southern Minnesota Energy Cooperative ("SMEC"), a
combined group of 12 neighboring electric cooperatives. Our Minnesota natural gas business is expected to be sold to Minnesota
Energy Resources Corporation, a subsidiary of Integrys Energy Group, Inc. The combined sales price of the electric and natural
gas assets is approximately $128 million, subject to customary closing adjustments. The sales of these assets require state and
federal approvals, which are expected to occur in six to twelve months.
The electric sales agreement also includes a ten-year purchased power agreement ("PPA") between SMEC and us. With the
PPA, our current Minnesota electric customers will continue to receive energy from a diverse portfolio of generation resources
while our future electric generation needs and plans are unchanged. We will continue to own and operate our electric generation
facilities in Minnesota.

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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
$250.0 million aggregate principal amount of 4.70% senior debentures due
2043.

Maturity
October 15, 2043.

Interest payment dates
April 15 and October 15 of each year, beginning on April 15, 2014.

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.

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 April 15, 2043, at the redemption prices
described in "Description of Senior Debentures--Optional Redemption." The
senior debentures will be redeemable, at our option, in whole or in part at any
time on or after April 15, 2043, at a redemption price equal to 100% of the
principal amount of the senior debentures being redeemed plus accrued and
unpaid interest to, but not including, the date of redemption.

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 $245.8 million, after deducting the underwriting discount and
estimated offering expenses payable by us. We intend to use the proceeds from
this offering to reduce outstanding capital under our receivables purchase and
sale program, reduce commercial paper classified as long-term debt and for
general corporate purposes.

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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."

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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, 2013 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,

2010

2011

2012

2012
2013

(In millions)

Income Statement Data:

Operating revenues

$1,795.8 $1,740.1 $ 1,650.3 $ 759.4 $ 861.3
Operating income

261.9

208.4

200.3

59.3

75.8

Net income

143.4

139.3

150.2

18.1

56.2

Earnings available for common stock

128.0

124.3

137.6

11.9

45.1

As at June

As at December 31,

30,

2011

2012

2013

(In millions)

Balance Sheet Data:

Current assets

$ 323.1
$
391.6
$ 431.0
Property, plant and equipment, net

3,676.1
3,858.2

3,962.9
Investments and other non-current assets

1,094.3
1,207.2

1,217.2
Current liabilities

422.5

468.8

527.8

Long-term debt, net

1,309.0
1,359.5

1,364.7
Other non-current liabilities

1,822.5
1,964.4

1,962.7
Ratio 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,
2008

2009

2010

2011

2012

2012

2013
4.05x

3.32x

3.23x

2.70x

2.64x

1.59x

2.13x

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