DEBT

The following table sets forth our consolidated debt for the periods indicated:



	December 31, 2017			December 31, 2016
	(Thousands of dollars)
ONEOK
Commercial paper outstanding, bearing a weighted-average interest rate of 2.23% (a)	$	614,673		$	—
Senior unsecured obligations:
$700,000 at 4.25% due February 2022	547,397			547,397
$500,000 at 7.5% due September 2023	500,000			500,000
$500,000 at 4.0% due July 2027	500,000			—
$100,000 at 6.5% due September 2028	—			87,126
$100,000 at 6.875% due September 2028	100,000			100,000
$400,000 at 6.0% due June 2035	400,000			400,000
$700,000 at 4.95% due July 2047	700,000			—
ONEOK Partners
Commercial paper outstanding (a)	—			1,110,277
Senior unsecured obligations:
$400,000 at 2.0% due October 2017	—			400,000
$425,000 at 3.2% due September 2018	425,000			425,000
$1,000,000 term loan, at 2.87% and 2.04%, respectively, due January 2019 (b)	500,000			1,000,000
$500,000 at 8.625% due March 2019	500,000			500,000
$300,000 at 3.8% due March 2020	300,000			300,000
$900,000 at 3.375 % due October 2022	900,000			900,000
$425,000 at 5.0 % due September 2023	425,000			425,000
$500,000 at 4.9 % due March 2025	500,000			500,000
$600,000 at 6.65% due October 2036	600,000			600,000
$600,000 at 6.85% due October 2037	600,000			600,000
$650,000 at 6.125% due February 2041	650,000			650,000
$400,000 at 6.2% due September 2043	400,000			400,000
Guardian Pipeline
Weighted average 7.85% due December 2022	36,607			44,257
Total debt	9,198,677			9,489,057
Unamortized portion of terminated swaps	18,468			20,186
Unamortized debt issuance costs and discounts	(78,193		)	(68,320		)
Current maturities of long-term debt	(432,650		)	(410,650		)
Short-term borrowings (c)	(614,673		)	(1,110,277		)
Long-term debt	$	8,091,629		$	7,919,996

(a) - In July 2017, the commercial paper outstanding under the ONEOK Partners commercial paper program was repaid as it matured with a combination of proceeds from new issuances from ONEOK’s recently established $2.5 billion commercial paper program, cash on hand and proceeds from our July 2017 $1.2 billion senior notes issuance. The $2.4 billion ONEOK Partners commercial paper program was terminated in July 2017.

(b) - The remaining $500 million of the Term Loan Agreement was repaid in January 2018.

(c) - Individual issuances of commercial paper under our commercial paper program generally mature in 90 days or less. These issuances are supported by and reduce the borrowing capacity under the $2.5 Billion Credit Agreement.

Debt Guarantees - Effective June 30, 2017, with the Merger Transaction, we, ONEOK Partners and the Intermediate Partnership issued, to the extent not already in place, guarantees of the indebtedness of ONEOK and ONEOK Partners.

$2.5 Billion Credit Agreement - In April 2017, we entered into the $2.5 Billion Credit Agreement with a syndicate of banks, which became effective June 30, 2017, with the close of the Merger Transaction and the terminations of the ONEOK Credit Agreement and ONEOK Partners Credit Agreement. The $2.5 Billion Credit Agreement is a $2.5 billion revolving credit facility and contains certain financial, operational and legal covenants. Among other things, these covenants include maintaining a ratio of indebtedness to adjusted EBITDA (EBITDA, as defined in our $2.5 Billion Credit Agreement, adjusted for all noncash charges and increased for projected EBITDA from certain lender-approved capital expansion projects) of no more than 5.75 to 1 at December 31, 2017; 5.5 to 1 for the subsequent two quarters; and 5.0 to 1 thereafter. Once the covenant decreases to 5.0 to 1, if we consummate one or more acquisitions in which the aggregate purchase is $25 million or more, the allowable ratio of indebtedness to adjusted EBITDA will increase to 5.5 to 1 for the quarter in which the acquisition is completed and the two following quarters.

The $2.5 Billion Credit Agreement includes a $100 million sublimit for the issuance of standby letters of credit and a $200 million sublimit for swingline loans. Under the terms of the $2.5 Billion Credit Agreement, we may request an increase in the size of the facility to an aggregate of $3.5 billion by either commitments from new lenders or increased commitments from existing lenders. The $2.5 Billion Credit Agreement contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in our credit ratings. Based on our current credit ratings, borrowings, if any, will accrue at LIBOR plus 110 basis points, and the annual facility fee is 15 basis points. We have the option to request two one-year extensions, subject to lender approval, which may be used for working capital, capital expenditures, acquisitions and mergers, the issuance of letters of credit and for other general corporate purposes. At December 31, 2017, our ratio of indebtedness to adjusted EBITDA was 4.5 to 1, and we were in compliance with all covenants under the $2.5 Billion Credit Agreement.

At December 31, 2017, we had $15.8 million of letters of credit issued and no borrowings outstanding under the $2.5 Billion Credit Agreement. At December 31, 2016, ONEOK had $1.1 million letters of credit issued and no borrowings outstanding under the ONEOK Credit Agreement, and ONEOK Partners had $14.0 million of letters of credit issued and no borrowings outstanding under the ONEOK Partners Credit Agreement.

Senior Unsecured Obligations - All notes are senior unsecured obligations, ranking equally in right of payment with all of our existing and future unsecured senior indebtedness, and are structurally subordinate to any of the existing and future debt and other liabilities of any nonguarantor subsidiaries.

Issuances - In July 2017, we completed an underwritten public offering of $1.2 billion senior unsecured notes consisting of $500 million, 4.0 percent senior notes due 2027, and $700 million, 4.95 percent senior notes due 2047. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $1.2 billion. The proceeds were used for general corporate purposes, which included repayment of existing indebtedness and capital expenditures.

In 2016, ONEOK Partners entered into the $1.0 billion senior unsecured Term Loan Agreement with a syndicate of banks maturing in 2019, bears interest at LIBOR plus 130 basis points based on our current credit ratings, allows prepayment without penalty or premium and contains substantially the same covenants as our $2.5 Billion Credit Agreement. As of January 2018, all amounts outstanding under the Term Loan Agreement have been repaid. See “repayments” section below.

In August 2015, we completed an underwritten public offering of $500 million, 7.5 percent senior notes due 2023. The net proceeds, after deducting underwriting discounts, commissions and other expenses, were $487.1 million. We used the proceeds together with cash on hand to purchase $650 million of additional common units from ONEOK Partners.

In March 2015, ONEOK Partners completed an underwritten public offering of $800 million of senior notes, consisting of $300 million, 3.8 percent senior notes due 2020, and $500 million, 4.9 percent senior notes due 2025. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $792.3 million and were used to repay amounts outstanding under its commercial paper program and for general partnership purposes.

Repayments - We repaid $500 million in both January 2018 and July 2017 on the Term Loan Agreement due 2019 with a combination of cash on hand and short-term borrowings. As of January 2018, all amounts outstanding under the Term Loan Agreement have been repaid.

In September 2017, we repaid ONEOK Partners’ $400 million, 2.0 percent senior notes due in October 2017 with a combination of cash on hand and short-term borrowings.

In July 2017, we redeemed our 6.5 percent senior notes due 2028 at a redemption price of $87.0 million, including the outstanding principal amount, plus accrued and unpaid interest, with cash on hand.

In October 2016, ONEOK Partners repaid its $450 million, 6.15 percent senior notes at maturity with a combination of cash on hand and short-term borrowings.

The aggregate maturities of long-term debt outstanding as of December 31, 2017, for the years 2018 through 2022 are shown below:



	Senior Notes		Guardian Pipeline		Total

2018	$	425.0	$	7.7	$	432.7
2019 (a)	$	1,000.0	$	7.7	$	1,007.7
2020	$	300.0	$	7.7	$	307.7
2021	$	—	$	7.7	$	7.7
2022	$	1,447.4	$	5.8	$	1,453.2

(a) $500 million of the $1.0 billion maturing in 2019 relates to the Term Loan Agreement, which was repaid in January 2018.

ONEOK covenants - The indentures governing ONEOK’s 6.875 percent senior notes due 2028 include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the senior notes due 2022, 2023, 2027, 2035 and 2047 include an event of default upon the acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding senior notes due 2022, 2023, 2027, 2028, 2035 and 2047 to declare those senior notes immediately due and payable in full. The indenture for the notes due 2023 also contains a provision that allows the holders of the notes to require ONEOK to offer to repurchase all or any part of their notes if a change of control and a credit rating downgrade occur at a purchase price of 101 percent of the principal amount, plus accrued and unpaid interest, if any.

ONEOK may redeem its senior notes, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK may redeem the remaining balance of its senior notes due 2022, 2023, 2027 and 2047 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting three to six months before the maturity date as stipulated in the respective contract terms. ONEOK’s senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK’s existing and future unsecured senior indebtedness.

ONEOK Partners covenants - ONEOK Partners’ senior notes are governed by an indenture containing covenants including, among other provisions, limitations on ONEOK Partners’ ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partners’ outstanding senior notes to declare those notes immediately due and payable in full.

The senior notes may be redeemed, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The senior notes due 2018, 2020, 2022, 2023, 2025, 2041 and 2043 may be redeemed at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one to six months before their maturity dates as stipulated in the respective contract terms.

Guardian Pipeline Senior Notes - These senior notes were issued under a master shelf agreement dated November 8, 2001, with certain financial institutions. Principal payments are due quarterly through 2022. Guardian Pipeline’s senior notes contain financial covenants that require the maintenance of certain financial ratios as defined in the master shelf agreement based on Guardian Pipeline’s financial position and results of operations. Upon any breach of these covenants, all amounts outstanding under the master shelf agreement may become due and payable immediately. At December 31, 2017, Guardian Pipeline was in compliance with its financial covenants.

Other - We amortize premiums, discounts and expenses incurred in connection with the issuance of long-term debt consistent with the terms of the respective debt instrument.