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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-Q

For the quarterly period ended March 31, 2015

OR

Commission File Number: 1-10982

Cross Timbers Royalty Trust

(Exact name of registrant as specified in its charter)

(855) 588-7839

(Registrant’s telephone number, including area code)

NONE

(Former name, former address and former fiscal year, if change since last report)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  ¨    No  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act (check one):

Indicate by check mark whether the registrant is a shell company (as defined in Exchange Act Rule 12b-2).    Yes  ¨    No  x

Indicate the number of units of beneficial interest outstanding, as of the latest practicable date:

Outstanding as of April 1, 2015

6,000,000

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CROSS TIMBERS ROYALTY TRUST

FORM 10-Q FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2015

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CROSS TIMBERS ROYALTY TRUST

GLOSSARY OF TERMS

The following are definitions of significant terms used in this Form 10-Q:

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CROSS TIMBERS ROYALTY TRUST

PART I - FINANCIAL INFORMATION

Item 1. Financial Statements.

The condensed financial statements included herein are presented, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and footnote disclosures normally included in annual financial statements have been condensed or omitted pursuant to such rules and regulations, although the trustee believes that the disclosures are adequate to make the information presented not misleading. These condensed financial statements should be read in conjunction with the financial statements and the notes thereto included in the trust’s latest Annual Report on Form 10-K. In the opinion of the trustee, all adjustments, consisting only of normal recurring adjustments, necessary to present fairly the assets, liabilities and trust corpus of the Cross Timbers Royalty Trust at March 31, 2015, and the distributable income and changes in trust corpus for the three-month periods ended March 31, 2015 and 2014, have been included. Distributable income for such interim periods is not necessarily indicative of distributable income for the full year. The condensed financial statements as of March 31, 2015, and for the three-month periods ended March 31, 2015 and 2014 have been subjected to a review by PricewaterhouseCoopers LLP, the trust’s independent registered public accounting firm, whose report is included herein.

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Report of Independent Registered Public Accounting Firm

To the Unitholders of Cross Timbers Royalty Trust and

Southwest Bank, Trustee:

We have reviewed the accompanying condensed statement of assets, liabilities and trust corpus of Cross Timbers Royalty Trust (the “Trust”) as of March 31, 2015, and the related condensed statements of distributable income and changes in trust corpus for the three-month periods ended March 31, 2015 and 2014. These interim financial statements are the responsibility of the Trustee.

We conducted our review in accordance with the standards of the Public Company Accounting Oversight Board (United States). A review of interim financial information consists principally of applying analytical procedures and making inquiries of persons responsible for financial and accounting matters. It is substantially less in scope than an audit conducted in accordance with the standards of the Public Company Accounting Oversight Board (United States), the objective of which is the expression of an opinion regarding the financial statements taken as a whole. Accordingly, we do not express such an opinion.

As described in Note 1, these financial statements were prepared on the modified cash basis of accounting, which is a comprehensive basis of accounting other than accounting principles generally accepted in the United States of America.

Based on our review, we are not aware of any material modifications that should be made to the accompanying condensed interim financial statements for them to be in conformity with the basis of accounting described in Note 1.

We previously audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), the statement of assets, liabilities and trust corpus as of December 31, 2014, and the related statements of distributable income and changes in trust corpus for the year then ended (not presented herein), and in our report dated March 6, 2015, we expressed an unqualified opinion on those financial statements. In our opinion, the information set forth in the accompanying condensed statement of assets, liabilities and trust corpus as of December 31, 2014 is fairly stated in all material respects in relation to the statement of assets, liabilities and trust corpus from which it has been derived.

/s/ PricewaterhouseCoopers LLP

Houston, TX

May 5, 2015

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CROSS TIMBERS ROYALTY TRUST

Condensed Statements of Assets, Liabilities and Trust Corpus

The accompanying notes to condensed financial statements are an integral part of these statements.

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CROSS TIMBERS ROYALTY TRUST

Condensed Statements of Distributable Income (Unaudited)

The accompanying notes to condensed financial statements are an integral part of these statements.

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CROSS TIMBERS ROYALTY TRUST

Condensed Statements of Changes in Trust Corpus (Unaudited)

The accompanying notes to condensed financial statements are an integral part of these statements.

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CROSS TIMBERS ROYALTY TRUST

Notes to Condensed Financial Statements (Unaudited)

1. Basis of Accounting

The financial statements of Cross Timbers Royalty Trust are prepared on the following basis and are not intended to present financial position and results of operations in conformity with U.S. generally accepted accounting principles (“GAAP”):

Costs deducted in the calculation of net proceeds for the 90% net profits interests generally include applicable taxes, transportation, marketing and legal costs, and do not include production expense or development costs. For the 75% net profits interests, costs deducted in the calculation of net proceeds include production expense, development costs, applicable taxes, transportation, marketing and legal costs, operating charges and other costs.

The financial statements of the trust differ from those prepared in conformity with U.S. GAAP because revenues are recognized when received rather than accrued in the month of production, expenses are recognized when paid rather than when incurred, and certain cash reserves may be established by the trustee for contingencies which would not be recorded under U.S. GAAP. This

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comprehensive basis of accounting other than U.S. GAAP corresponds to the accounting permitted for royalty trusts by the U.S. Securities and Exchange Commission, as specified by Staff Accounting Bulletin Topic 12:E, Financial Statements of Royalty Trusts.

Most accounting pronouncements apply to entities whose financial statements are prepared in accordance with U.S. GAAP, directing such entities to accrue or defer revenues and expenses in a period other than when such revenues were received or expenses were paid. Because the trust’s financial statements are prepared on the modified cash basis, as described above, most accounting pronouncements are not applicable to the trust’s financial statements.

The initial carrying value of the net profits interests of $61,100,449 represents XTO Energy’s historical net book value for the interests on February 12, 1991, the creation date of the trust. Amortization of the net profits interests is calculated on a unit-of-production basis and is charged directly to trust corpus. Accumulated amortization was $50,232,556 as of March 31, 2015 and $50,106,151 as of December 31, 2014.

2. Income Taxes

For federal income tax purposes, the trust constitutes a fixed investment trust that is taxed as a grantor trust. A grantor trust is not subject to tax at the trust level. Accordingly, no provision for income taxes has been made in the financial statements. The unitholders are considered to own the trust’s income and principal as though no trust were in existence. The income of the trust is deemed to have been received or accrued by each unitholder at the time such income is received or accrued by the trust and not when distributed by the trust.

All revenues from the trust are from sources within Texas, Oklahoma or New Mexico. Because it distributes all of its net income to unitholders, the trust has not been taxed at the trust level in New Mexico or Oklahoma. While the trust has not owed tax, the trustee is required to file a return with Oklahoma reflecting the income and deductions of the trust attributable to properties located in that state, along with a schedule that includes information regarding distributions to unitholders. Texas does not impose a state income tax, so no part of the trust’s income will be subject to income tax at the trust level in Texas.

Each unitholder should consult his or her own tax advisor regarding income tax requirements, if any, applicable to such person’s ownership of trust units.

Unitholders should consult the trust’s latest annual report on Form 10-K for a complete discussion of federal and state tax matters.

3. Contingencies

Several states have enacted legislation requiring state income tax withholding from nonresident recipients of oil and gas proceeds. After consultation with its tax counsel, the trustee believes that it is not required to withhold on payments made to the unitholders. However, regulations are subject to change by the various states, which could change this conclusion. Should amounts be withheld on payments made to the trust or the unitholders, distributions to the unitholders would be reduced by the required amount, subject to the filing of a claim for refund by the trust or unitholders for such amount.

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4. Excess Costs

XTO Energy advised the trustee that lower oil prices and increased costs caused costs to exceed revenues by a total of $405,868 ($304,401 net to the trust) in January and March 2015 and lower oil prices caused costs to exceed revenues by a total of $4,469 ($3,352 net to the trust) in February 2015 on properties underlying the Texas working interest. However, these excess costs did not reduce net proceeds from the remaining conveyances.

XTO Energy advised the trustee that lower oil prices caused costs to exceed revenues by a total of $43,414 ($32,560 net to the trust) in March 2015 on properties underlying the Oklahoma working interest. However, these excess costs did not reduce net proceeds from the remaining conveyances.

Cumulative excess costs for the Texas and Oklahoma working interest conveyances remaining as of March 31, 2015 totaled $507,722 ($380,791 net to the trust).

Lower oil prices caused costs to exceed revenues by a total of $42,061 ($31,546 net to the trust) on properties underlying the Texas working interest in January 2014. However, these excess costs did not reduce net proceeds from the remaining conveyances. XTO advised the trustee that higher oil prices and decreased costs led to the full recovery of excess costs, plus accrued interest, of $42,177 ($31,633 net to the trust) in February 2014.

5. Other Proceeds

The calculation of net profits income for the quarter ended March 31, 2014 included $519,071 ($467,164 net to the trust), which includes interest of $210,242 ($189,218 net to the trust), related to a one-time purchaser refund for deductions attributable to coal seam gas wells located in the San Juan Basin for the period December 1997 through May 2006.

Item 2. Trustee’s Discussion and Analysis.

The following discussion should be read in conjunction with the trustee’s discussion and analysis contained in the trust’s 2014 Annual Report on Form 10-K, as well as the condensed financial statements and notes thereto included in this Quarterly Report on Form 10-Q. The trust’s Annual Report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and all amendments to those reports are available on the trust’s web site at www.crt-crosstimbers.com.

Distributable Income

For the quarter ended March 31, 2015, net profits income was $2,824,371 compared to $4,386,145 for first quarter 2014. This 36% decrease in net profits income is primarily the result of lower oil and gas prices ($1.7 million), a one-time purchaser refund included in 2014 ($0.5 million) and decreased gas production ($0.3 million), partially offset by decreased taxes, transportation and other costs ($0.4 million), excess costs on the Texas and Oklahoma working interest properties in 2015 ($0.3 million) and lower development costs ($0.2 million). See “Net Profits Income” below.

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After considering interest income of $12 and administration expense of $258,393, distributable income for the quarter ended March 31, 2015 was $2,565,990, or $0.427665 per unit of beneficial interest. Administration expense for the quarter increased $76,151 from the prior year quarter. Administration expense for the first quarter of 2015 included $100,000, which the trustee reserved for administrative expenses. For first quarter 2014, distributable income was $4,203,960, or $0.700660 per unit. Distributions to unitholders for the quarter ended March 31, 2015 were:

Net Profits Income

Net profits income is recorded when received by the trust, which is the month following receipt by XTO Energy, and generally two months after oil production and three months after gas production. Net profits income is generally affected by three major factors:

Because properties underlying the 90% net profits interests are royalty and overriding royalty interests, the calculation of net profits income from these interests only includes deductions for production and property taxes, legal costs, and marketing and transportation charges. In addition to these costs, the calculation of net profits income from the 75% net profits interests includes deductions for production expense and development costs since the related underlying properties are working interests.

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The following is a summary of the calculation of net profits income received by the trust:

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The following are explanations of significant variances on the underlying properties from first quarter 2014 to first quarter 2015:

Sales Volumes

Oil

Oil sales volumes increased 6% from first quarter 2014 to first quarter 2015 primarily because of increased production from new wells and workovers and the timing of cash receipts, partially offset by natural production decline.

Gas

Gas sales volumes decreased 15% from first quarter 2014 to first quarter 2015 primarily because of the timing of cash receipts and natural production decline, partially offset by increased production from new wells and workovers.

The estimated rate of natural production decline on the underlying oil and gas properties is approximately 6% to 8% a year.

Sales Prices

Oil

The first quarter 2015 average oil price was $62.80 per Bbl, a 30% decrease from the first quarter 2014 average price of $90.14 per Bbl. Oil prices are expected to remain volatile. The first quarter 2015 oil price is primarily related to production from November 2014 through January 2015, when the average NYMEX price was $60.89 per Bbl. The average NYMEX price for February and March 2015 was $49.80 per Bbl. At April 28, 2015, the average NYMEX futures price for the following twelve months was $60.84 per Bbl.

Gas

The first quarter 2015 average gas price was $5.71 per Mcf, an 18% decrease from the first quarter 2014 average price of $6.94 per Mcf. Natural gas prices are affected by natural gas liquids prices, the level of North American production, weather, crude oil, the U.S. economy, storage levels and import levels of liquefied natural gas. Natural gas prices are expected to remain volatile. The first quarter 2015 gas price is primarily related to production from October through December 2014, when the average NYMEX price was $4.00 per MMBtu. The average NYMEX price for January through March 2015 was $2.98 per MMBtu. At April 28, 2015, the average NYMEX futures price for the following twelve months was $2.79 per MMBtu.

Costs

Taxes, Transportation and Other

Taxes, transportation and other decreased 21% for the first quarter primarily because of decreased oil and gas production taxes and other deductions related to lower oil and gas revenues, partially offset by a one-time purchaser refund for coal seam gas deductions included in 2014 and increased property taxes related to increased valuations.

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Production Expense

Production expense increased 22% for the first quarter primarily because of increased outside operated, repairs and maintenance and labor costs, partially offset by decreased non-operated overhead costs.

Development Costs

Development costs decreased 32% for the first quarter primarily because of the timing of cash expenditures and decreased activity and costs related to non-operated Texas and Oklahoma oil properties underlying the 75% net profits interests.

XTO advised the trustee that unit operators for the underlying Texas and Oklahoma working interest oil properties have reported revised 2015 budgeted development costs of $4.4 million, a decrease from $5.9 million previously reported in the 2014 Annual Report on Form 10-K.

Excess Costs

XTO Energy advised the trustee that lower oil prices and increased costs caused costs to exceed revenues by a total of $405,868 ($304,401 net to the trust) in January and March 2015 and lower oil prices caused costs to exceed revenues by a total of $4,469 ($3,352 net to the trust) in February 2015 on properties underlying the Texas working interest. However, these excess costs did not reduce net proceeds from the remaining conveyances.

XTO Energy advised the trustee that lower oil prices caused costs to exceed revenues by a total of $43,414 ($32,560 net to the trust) in March 2015 on properties underlying the Oklahoma working interest. However, these excess costs did not reduce net proceeds from the remaining conveyances.

Cumulative excess costs for the Texas and Oklahoma working interest conveyances remaining as of March 31, 2015 totaled $507,722 ($380,791 net to the trust).

Lower oil prices caused costs to exceed revenues by a total of $42,061 ($31,546 net to the trust) on properties underlying the Texas working interest in January 2014. However, these excess costs did not reduce net proceeds from the remaining conveyances. XTO advised the trustee that higher oil prices and decreased costs led to the full recovery of excess costs, plus accrued interest, of $42,177 ($31,633 net to the trust) in February 2014.

Other Proceeds

The calculation of net profits income for the quarter ended March 31, 2014 included $519,071 ($467,164 net to the trust), which includes interest of $210,242 ($189,218 net to the trust), related to a one-time purchaser refund for deductions attributable to coal seam gas wells located in the San Juan Basin for the period December 1997 through May 2006.

Contingencies

Several states have enacted legislation requiring state income tax withholding from nonresident recipients of oil and gas proceeds. After consultation with its tax counsel, the trustee believes that it is not required to withhold on payments made to the unitholders. However, regulations are subject to change by the various states, which could change this conclusion. Should amounts be withheld on payments made to the trust or the unitholders, distributions to the unitholders would be reduced by the required amount, subject to the filing of a claim for refund by the trust or unitholders for such amount.

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Forward-Looking Statements

Statements in this report relating to future plans, predictions, events or conditions are forward-looking statements. All statements other than statements of historical fact included in this Form 10-Q including, without limitation, statements regarding the net profits interests, underlying properties, development activities, development, production and other costs and expenses, oil and gas prices and differentials to NYMEX prices, distributions to unitholders, industry and market conditions and the satisfaction or waiver of conditions to the trustee’s resignation, are forward-looking statements that are subject to risks and uncertainties which are detailed in Part I, Item 1A of the trust’s Annual Report on Form 10-K for the year ended December 31, 2014, which is incorporated by this reference as though fully set forth herein. XTO Energy and the trustee assume no duty to update these statements as of any future date.

Item 3. Quantitative and Qualitative Disclosures about Market Risk.

There have been no material changes in the trust’s market risks from the information disclosed in Part II, Item 7A of the trust’s Annual Report on Form 10-K for the year ended December 31, 2014.

Item 4. Controls and Procedures.

As of the end of the period covered by this report, the trustee carried out an evaluation of the effectiveness of the trust’s disclosure controls and procedures pursuant to Exchange Act Rules 13a-15 and 15d-15. Based upon that evaluation, the trustee concluded that the trust’s disclosure controls and procedures are effective in timely recording, processing, summarizing and reporting, on a timely basis, information required to be disclosed by the trust in the reports that it files or submits under the Securities Exchange Act of 1934 and are effective in ensuring that information required to be disclosed by the trust in the reports that it files or submits under the Securities Exchange Act of 1934 is accumulated and communicated to the trustee to allow timely decisions regarding required disclosure. In its evaluation of disclosure controls and procedures, the trustee has relied, to the extent considered reasonable, on information provided by XTO Energy. There has not been any change in the trust’s internal control over financial reporting during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the trust’s internal control over financial reporting.

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PART II—OTHER INFORMATION

Item 1.

  Not applicable.

Item 1A. Risk Factors.

There have been no material changes in the risk factors disclosed under Part I, Item 1A of the trust’s Annual Report on Form 10-K for the year ended December 31, 2014.

Items 2 through 5.

Not applicable.

Item 6. Exhibits.

(a) Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this Report to be signed on its behalf by the undersigned thereunto duly authorized.

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