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EXHIBIT 99-10

SUPPLEMENTARY OIL AND GAS DISCLOSURE (unaudited)

The following disclosures are presented in accordance with United States Financial Accounting Standards Board ("FASB") Topic 932 — "Extractive Activities — Oil and Gas" and Subpart 1200 of Regulation S-K ("Subpart 1200") of the United States Securities and Exchange Commission. Disclosures pertaining to the audited consolidated financial statements as at and for the year ended December 31, 2015 (the "2015 Financial Statements") of Suncor Energy Inc. ("Suncor" or the "Company") were prepared in accordance with International Financial Reporting Standards as issued by the International Accounting Standards Board and Canadian generally accepted accounting principles contained within Part 1 of the Chartered Professional Accountants Canada Handbook, which differ in material respects from financial statements prepared in accordance with United States generally accepted accounting principles. The 2015 Financial Statements are attached as Exhibit 99.1 to Suncor's annual report on Form 40-F for the year ended December 31, 2015 (the "Form 40-F").

Reserves Data

Reserves data included herein are estimates only and can be significantly impacted by a variety of internal and external factors. For more information to the risks involved when estimating reserves, see the discussion in the "Statement of Reserves Data and Other Oil and Gas Information — Significant Risk Factors or Uncertainties Affecting Reserves Data" section in Suncor's 2015 Annual Information Form (the "2015 AIF"), which is contained in the Form 40-F. Readers should also see Suncor's Management's Discussion and Analysis for the year ended December 31, 2015, which is attached as Exhibit 99.2 to the Form 40-F (the "2015 Management's Discussion and Analysis").

The reserves data presented herein may differ in relation to the format and the basis from which volumes are economically determined under Subpart 1200 and National Instrument 51-101 — "Standards of Disclosure of Oil and Gas Activities" ("NI 51-101"), as disclosed in the 2015 AIF. Subpart 1200 requires disclosure of net proved reserves, after royalties, using the average of the first-day-of-the-month prices for the twelve month period prior to the end of the reporting period, whereas NI 51-101 requires disclosure of gross and net reserves, estimated using forecast prices and costs.

Net Proved Oil and Gas Reserves⁽¹⁾⁽²⁾

The majority of Suncor's oil and gas reserves are in Canada. In order to align with the Company's segmented information in the 2015 Financial Statements, the 2015 Management's Discussion and Analysis and the 2015 AIF, the Company presents the following supplementary oil and gas disclosures by showing amounts associated with its Oil Sands segment, which are exclusively in Canada and produce synthetic crude oil ("SCO") and bitumen, separate from other Canadian operations, which are aggregated with Suncor's international operations (collectively, "Exploration and Production") and produce crude oil, natural gas and natural gas liquids ("NGLs"). Exploration and Production reserves are in onshore and offshore Canada, offshore UK and onshore Libya.

	SCO (mmbbls)				Bitumen (mmbbls)				Crude Oil and NGLs⁽³⁾ (mmbbls)				Natural Gas (bcf)				Total (mmboe)

At December 31, (net reserves, constant prices and costs)	2015		2014		2015		2014		2015		2014		2015		2014		2015		2014
Proved Developed
Oil Sands		1 823		1 700		99		143		—		—		—		—		1 922		1 843
Exploration and Production		—		—		—		—		120		170		21		36		124		176

		1 823		1 700		99		143		120		170		21		36		2 046		2 019

Proved Undeveloped
Oil Sands		567		452		454		1 444		—		—		—		—		1 022		1 897
Exploration and Production		—		—		—		—		32		64		1		1		32		64

		567		452		454		1 444		32		64		1		1		1 054		1 961

Proved
Oil Sands		2 390		2 152		554		1 588		—		—		—		—		2 944		3 740
Exploration and Production		—		—		—		—		153		234		21		37		156		241

		2 390		2 152		554		1 588		153		234		21		37		3 100		3 981

Reconciliation of Net Proved Oil and Gas Reserves

(net reserves, constant prices and costs)

Oil Sands
SCO (mmbbls)	2 320	(62	)	—	—	—	(106	)	—		2 152
Bitumen (mmbbls)	1 719	(92	)	—	—	—	(39	)	—		1 588
Exploration and Production
Crude oil and NGLs⁽³⁾ (mmbbls)	216	53		—	—	1	(32	)	(4	)	234
Natural gas (bcf)	44	8		—	—	6	(7	)	(14	)	37

Total (mmboe)	4 263	(100	)	—	—	2	(178	)	(6	)	3 981

(net reserves, constant prices and costs)

Oil Sands
SCO (mmbbls)	2 152	361		—	—	—	(124	)	—	2 390
Bitumen (mmbbls)	1 588	(993	)	—	—	—	(41	)	—	554
Exploration and Production
Crude oil and NGLs⁽³⁾ (mmbbls)	234	(45	)	—	—	—	(37	)	—	152
Natural gas (bcf)	37	(7	)	—	—	—	(9	)	—	21

Total (mmboe)	3 981	(678	)	—	—	—	(203	)	—	3 100

Notes to Reserve Data:

(1)

Definitions

a.: Net reserves, in relation to Suncor's production and reserves, represents the Company's working interest share after deduction of royalty obligations, plus the Company's royalty interests in production and reserves.
b.: Proved oil and gas reserves are those quantities of oil and gas, which, by analysis of geoscience and engineering data, can be estimated with reasonable certainty to be economically producible, from a given date forward, from known reservoirs, and under existing economic conditions, operating methods and government regulations.
c.: Proved developed oil and gas reserves are those quantities that can be expected to be recovered through existing wells with existing equipment and operating methods or in which the cost of the required equipment is relatively minor compared to the cost of a new well; and can be expected to be recovered through extraction equipment and infrastructure installed and operational at the time of the reserves estimate for projects that extract oil and gas by means not involving a well.
d.: Proved undeveloped oil and gas reserves are those quantities that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion.

(2)

Reserve data tables may not add due to rounding.

(3)

Natural gas liquids reserves are not significant and have been presented in combination with Crude Oil reserves.

(4)

Revisions of previous estimates include changes to proved reserves, resulting from new information (except for an increase in proved acreage) normally obtained from development drilling and production history or resulting from a change in economic factors, such as changes in constant prices used for the reserve evaluation.

(5)

Extensions and discoveries are additions to proved reserves from proved acreage of previously discovered reservoirs through additional drilling in periods subsequent to discovery or discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields.

Capitalized Costs

	At December 31, 2015									At December 31, 2014

($ millions)	Oil Sands			Exploration and Production			Total			Oil Sands			Exploration and Production			Total
Exploration and evaluation assets⁽¹⁾		1 198			483			1 681			1 581			667			2 248
Oil and gas properties⁽²⁾		13 387			19 248			32 635			12 584			16 651			29 235
Plant and equipment⁽²⁾		45 571			1 221			46 792			41 427			1 016			42 443
— accumulated provision⁽²⁾		(15 991	)		(11 810	)		(27 801	)		(13 032	)		(8 021	)		(21 053	)

Total		44 165			9 142			53 307			42 560			10 313			52 873

(1): Exploration and evaluation assets largely represent amounts associated with unproved properties, but may include properties with proved reserves for which Suncor's Board of Directors have not sanctioned development. See note 17 of the 2015 Financial Statements.
(2): Oil and Gas Properties, Plant and Equipment and the accumulated provision largely represent amounts associated with proved properties. See note 16 of the 2015 Financial Statements.

Costs Incurred for Property Acquisition, Exploration and Development Activities

	Year ended December 31, 2015						Year ended December 31, 2014

($ millions)	Oil Sands		Exploration and Production		Total		Oil Sands		Exploration and Production		Total
Unproved property acquisition		18		1		19		—		1		1
Proved property acquisition		360		—		360		—		—		—
Exploration⁽¹⁾		157		400		557		161		296		457
Development⁽²⁾		3 553		1 028		4 581		4 237		1 819		6 056

Total		4 088		1 429		5 517		4 398		2 116		6 514

(1): Includes amounts capitalized to Exploration and Evaluation as well as those charged to Exploration Expense on the Consolidated Balance Sheets and the Consolidated Statements of Comprehensive Income, respectively, of the 2015 Financial Statements.
(2): Includes amounts capitalized to Property, Plant and Equipment on the Consolidated Balance Sheets of the 2015 Financial Statements that relate to the Company's decommissioning and restoration activities.

Results of Operations for Oil- and Gas-Producing Activities

	At December 31, 2015									At December 31, 2014

($ millions)	Oil Sands			Exploration and Production			Total			Oil Sands		Exploration and Production			Total
Operating revenues, net of royalties		9 218			2 345			11 563			13 579		4 043			17 622
Other Income		146			150			296			115		217			332

		9 364			2 495			11 859			13 694		4 260			17 954
Purchases of crude oil and products		319			3			322			355		459			814
Operating, selling and general		5 220			502			5 722			6 042		558			6 600
Transportation		645			98			743			541		90			631
Depreciation, depletion, amortization and impairment		3 583			3 106			6 689			4 035		1 349			5 384
Exploration		120			358			478			96		271			367
Loss (gain) on disposal of assets		8			(5	)		3			3		(82	)		(79	)
Finance expenses		150			82			232			153		72			225

Earnings (Loss) before Income Taxes		(681	)		(1 649	)		(2 330	)		2 469		1 543			4 012
Income taxes		175			(891	)		(716	)		693		890			1 583

Net Earnings (Loss)		(856	)		(758	)		(1 614	)		1 776		653			2 429

Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves

The standardized measure of discounted future net cash flows relating to Suncor's proved oil and gas reserves are calculated in accordance with FASB Topic 932 — "Extractive Activities — Oil and Gas". Future cash inflows are estimated using the trailing twelve-month average price, which are also used in estimating the entity's proved oil and gas reserves. Future development and production costs, including the associated decommissioning and restoration activities, are calculated by estimating the expenditures to be incurred in developing and producing the proved oil and gas reserves at the end of the year, based on year-end costs and assuming continuation of existing economic conditions. The appropriate year-end statutory tax rates, with consideration of future tax rates already legislated, were applied to the future pretax net cash flows, less the tax basis of the properties involved. A prescribed rate of 10% is applied to discount the future net cash flows.

The calculation of the standardized measure of discounted future net cash flows is based upon information prepared by the Company's independent qualified reserves evaluators, and adjusted for decommissioning and restoration activities and future income taxes.

It should not be assumed that the estimates of future net cash flows presented in the tables below represent the fair market value of the reserves. There is no assurance that the price and cost assumptions will be attained and variances could be material. Future changes to income tax, royalty and environmental regulations could also have a significant impact on the respective assumptions. There is no guarantee that the estimates for SCO, bitumen, crude oil and NGLs, and natural gas reserves provided herein will be recovered. Actual SCO, bitumen, crude oil and NGLs, and natural gas reserves may be greater than or less than the estimates provided herein.

The following twelve-month average prices were used to calculate the standardized measure of discounted future net cash flows:

Year	Brent North Sea		WTI Cushing Oklahoma		WCS Hardisty Alberta		Light Sweet Edmonton Alberta		Pentanes Plus Edmonton Alberta		AECO Gas		B.C. Gas Westcoast Station 2		National Balancing Point North Sea

	US$/bbl		US$/bbl		Cdn$/bbl		Cdn$/bbl		Cdn$/bbl		Cdn$/mmbtu		Cdn$/mmbtu		Cdn$/mmbtu
2015		54.17		50.28		48.82		61.20		64.19		2.66		1.92		8.42
2014		101.70		94.99		82.80		95.98		103.40		4.65		4.32		9.52

	At December 31, 2015									At December 31, 2014

($ millions)	Oil Sands			Exploration and Production			Total			Oil Sands			Exploration and Production			Total
Future cash inflows		170 803			10 330			181 133			309 703			25 774			335 477
Future production costs		(99 211	)		(4 050	)		(103 261	)		(154 238	)		(6 122	)		(160 360	)
Future development costs		(54 936	)		(4 231	)		(59 167	)		(74 774	)		(4 394	)		(79 168	)
Future income tax expenses		(4 423	)		(982	)		(5 405	)		(18 212	)		(8 103	)		(26 315	)

Future net cash flows		12 233			1 067			13 300			62 479			7 155			69 634
10% Discount Factor		(6 560	)		264			(6 296	)		(39 279	)		(2 337	)		(41 616	)

Standardized measure of discounted future net cash flows		5 673			1 331			7 004			23 200			4 818			28 018

Changes in Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves

($ millions)

Standardized measure of discounted future net cash flows — beginning of year	28 018		24 383
Sales and transfers of oil and gas produced	(9 701	)	(8 679	)
Net change in sales prices and operating costs related to future production	(32 402	)	5 310
Net change due to extensions, discoveries and improved recovery	—		47
Net change due to acquisitions and dispositions	—		(72	)
Net change due to revisions in quantity estimates	1 287		52
Previously estimated development costs incurred during the period	2 533		5 209
Changes in estimated future development costs	3 283		(2 646	)
Accretion of discount	2 564		2 213
Net change in income taxes	11 422		2 201

Standardized measure of discounted future net cash flows — end of year	7 004		28 018

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EXHIBIT 99-10