Exhibit 99.1

Calgary, January 31, 2012

Imperial Oil announces estimated fourth quarter financial and operating results

Bruce March, chairman, president and chief executive officer of Imperial Oil, commented:

Imperial Oil’s earnings in the fourth quarter of 2011 were $1,005 million, up 26 percent from the fourth quarter of 2010. Strong operating performance in Imperial’s business segments allowed us to capture higher crude oil realizations in the Upstream and improved margins in the Downstream petroleum product markets. Another record quarterly production at Cold Lake highlighted our consistent focus on operations excellence and production reliability. The same focus in all areas of our business is fundamental to sustaining operating performance while advancing our company growth plans.

Earnings for the full year 2011 were $3,371 million, the second highest in our company’s history and up $1,161 million or 53% from $2,210 million in 2010.

The strength of Imperial’s business model and our flexibility to manage within changing business conditions continues to serve our shareholders well. We are entering the third year of our decade-long growth strategy in which we will double our total Upstream production to about 600,000 barrels per day. Capital expenditures in 2011 were $4.1 billion and were focused on advancing the construction of the Kearl oil sands project and funded from internally generated funds.

Imperial Oil is one of Canada’s largest corporations and a leading member of the country’s petroleum industry. The company is a major producer of crude oil and natural gas, Canada’s largest petroleum refiner, a key petrochemical producer and a leading marketer with coast-to-coast supply and retail service station networks.

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Fourth quarter items of interest

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Fourth quarter 2011 vs. fourth quarter 2010

The company’s net income for the fourth quarter of 2011 was $1,005 million or $1.18 a share on a diluted basis, compared with $799 million or $0.94 a share for the same period last year.

Earnings in the fourth quarter were higher than the same quarter in 2010 primarily due to higher crude oil commodity prices of about $275 million, increased Cold Lake bitumen production of about $70 million and stronger downstream margins of about $65 million. These factors were partially offset by the unfavourable impacts of lower Syncrude volumes of about $100 million, increased refinery maintenance totalling about $60 million, higher royalty costs of about $55 million and lower conventional crude oil volumes of about $30 million. Fourth quarter 2011 earnings also included higher gains of $95 million on primarily Upstream natural gas asset divestments partially offset by higher share-based compensation charges of about $30 million.

Upstream net income in the fourth quarter was $771 million, $245 million higher than the same period of 2010. Earnings benefited from higher crude oil commodity prices of about $275 million and increased Cold Lake bitumen production of about $70 million. These factors were partially offset by lower Syncrude volumes of about $100 million as a result of maintenance activities, higher royalty costs due to higher commodity prices of about $55 million, and lower conventional crude oil volumes of about $30 million due to natural reservoir decline. Included in fourth quarter 2011 earnings were gains of $112 million on asset divestments, about $95 million higher than the fourth quarter of 2010.

The average price of Brent crude oil in U.S. dollars, a common benchmark for world oil markets, was $109.29 a barrel in the fourth quarter of 2011, up about 26 percent from the corresponding period last year. Increases in the company’s average realizations in Canadian dollars on sales of conventional crude oil, synthetic crude oil and bitumen mirrored the same trend as Brent crude oil prices, compared to the same period last year.

Gross production of Cold Lake bitumen averaged 162 thousand barrels a day, equalling the production record achieved in the previous quarter. Cold Lake production was up ten percent from 147 thousand barrels in the same quarter last year. Increased volumes were due to contributions from new wells steamed in 2010 and 2011, increased recoveries as a result of technology applications and the cyclic nature of production at Cold Lake.

The company’s share of Syncrude’s gross production in the fourth quarter was 63 thousand barrels a day, versus 79 thousand barrels in the fourth quarter of 2010. Lower production was primarily the result of higher planned and unplanned maintenance activities.

Gross production of conventional crude oil averaged 20 thousand barrels a day in the fourth quarter, down from 24 thousand barrels in the fourth quarter of 2010. Lower volumes were primarily due to natural reservoir decline.

Gross production of natural gas during the fourth quarter of 2011 was 240 million cubic feet a day, down from 275 million cubic feet in the same period last year. The lower production volume was primarily a result of the impact of divested producing properties.

In the fourth quarter, the company sold its interests in shallow gas properties in the Medicine Hat, Alberta area and the Coleville-Hoosier natural gas producing property in Saskatchewan, realizing a gain of about $72 million. Natural gas production for the company’s share of the properties averaged about 52 million cubic feet a day in 2010. Also in the quarter, the company recorded a gain of about $40 million from an exchange of oil sands leases with third parties.

Downstream net income was $272 million in the fourth quarter of 2011, compared with $266 million in the same period a year ago. Earnings increased primarily due to stronger overall margins of about $65 million partially offset by the unfavourable impact of higher maintenance activities on refinery operations and expenses totalling about $60 million.

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Fourth quarter 2011 vs. fourth quarter 2010 (continued)

Chemical net income was $11 million in the fourth quarter, compared with $25 million in the same quarter last year. Earnings in the fourth quarter were negatively impacted by lower margins for polyethylene products and lower sales volume for intermediate products partially offset by higher margins for intermediate and aromatic products.

Net income effects from Corporate and other were negative $49 million in the fourth quarter, compared with negative $18 million in the same period of 2010. Unfavourable effects were primarily due to changes in share-based compensation charges.

Cash flow generated from operating activities was $1,216 million in the fourth quarter of 2011, an increase of $212 million from the corresponding period in 2010, and in line with the earnings increase versus the fourth quarter of 2010.

Investing activities used net cash of $833 million in the fourth quarter, compared with $992 million in the same period of 2010. Cash used for property, plant and equipment additions was $1,107 million in the fourth quarter, compared with $1,045 million during the same quarter 2010. For the Upstream segment, expenditures during the quarter were primarily directed towards the advancement of the Kearl initial development and Kearl expansion oil sands projects. Other investments included advancing the Nabiye expansion project at Cold Lake, environmental and efficiency projects at Syncrude, as well as the advancement of the production pilot at Horn River and tight oil acreage acquisitions. The Downstream segment’s capital expenditures were focused mainly on refinery projects to improve reliability, feedstock flexibility, energy efficiency and environmental performance. Proceeds from asset sales were $270 million in the fourth quarter, $221 million higher than the fourth quarter of 2010.

The company’s cash balance was $1,202 million at December 31, 2011, up $935 million from $267 million at the end of 2010.

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Full year highlights

Full year 2011 vs. full year 2010

Net income in 2011 was $3,371 million or $3.95 a share on a diluted basis, versus $2,210 million or $2.59 a share in 2010.

For the full year 2011, increased earnings were primarily attributable to higher crude oil commodity prices of about $925 million, stronger industry refining margins of about $590 million and increased Cold Lake bitumen production of about $260 million. These factors were partially offset by the unfavourable impacts of higher royalty costs of about $245 million, the stronger Canadian dollar of about $205 million, and lower conventional crude oil volumes of about $150 million, about $80 million of which was due to third party pipeline reliability issues. 2011 earnings also included higher gains of about $70 million on asset divestments.

Upstream net income for the year was $2,457 million, up $693 million from 2010. Earnings increased primarily due to the impacts of higher crude oil commodity prices of about $925 million and increased Cold Lake bitumen production of about $260 million. These factors were partially offset by the unfavourable effects of higher royalty costs of about $245 million, the stronger Canadian dollar of about $150 million and lower conventional crude oil volumes of about $150 million, of which about $80 million was a result of the second and third quarter 2011 third-party pipeline issues. Included in 2011 earnings were gains of $116 million on asset divestments, about $95 million higher than 2010.

The average price of Brent crude oil in U.S. dollars, a common benchmark for Atlantic Basin oil markets, was $111.29 a barrel in 2011, up about 40 percent from the previous year. Increase in the average price of West Texas Intermediate (WTI) crude oil, a common benchmark for mid-continent North American oil markets, was limited to 19 percent due to the continued weakness in WTI crude oil markets. Increases in the company’s average realizations on sales of Canadian conventional crude oil and synthetic crude oil were in line with that of WTI. The company’s average bitumen realizations in Canadian dollars in 2011 increased ten percent to $63.95 per barrel as the price spread between light crude oil and Cold Lake bitumen widened.

Gross production of Cold Lake bitumen was a record 160 thousand barrels a day this year, compared with 144 thousand barrels in the 2010. Increased volumes were due to contributions from new wells steamed in 2010 and 2011, increased recoveries as a result of technology applications and the cyclic nature of production at Cold Lake.

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Full year 2011 vs. full year 2010 (continued)

During the year, the company’s share of gross production from Syncrude averaged 72 thousand barrels a day, in line with 73 thousand barrels in 2010.

In 2011, gross production of conventional crude oil was 18 thousand barrels a day, compared with 23 thousand barrels in 2010. Lower volumes were primarily due to third-party pipeline downtime, which reduced production at the Norman Wells field, along with natural reservoir decline.

Gross production of natural gas in 2011 was 254 million cubic feet a day, down from 280 million cubic feet in 2010. The lower production volume was primarily a result of natural reservoir decline.

In 2011, Downstream net income was $884 million, an increase of $442 million over 2010. Higher earnings were primarily due to the favourable impact of stronger industry refining margins of about $590 million. This factor was partially offset by the unfavourable impacts of higher maintenance activities on refinery operations and expenses totalling about $60 million and the stronger Canadian dollar of about $55 million. Earnings in 2010 included a gain of about $25 million from sale of non-operating assets.

Chemical net income in 2011 was $122 million, up $53 million from 2010. Improved margins for intermediate and aromatic products, lower costs due to lower planned maintenance activities and higher polyethylene sales volumes were the main contributors to the increase. These factors were partially offset by lower margins for polyethylene products.

In 2011, net income effects from Corporate and other were negative $92 million, compared with negative $65 million in 2010. Unfavourable effects were primarily due to changes in share-based compensation charges.

Key financial and operating data follow.

Forward-Looking Statements

Statements in this report relating to future plans, projections, events or conditions are forward-looking statements. Actual future results, including project plans, costs, timing and capacities; financing sources; the resolution of contingencies and uncertain tax positions; the effect of changes in prices and other market conditions; and environmental and capital expenditures could differ materially depending on a number of factors, such as the outcome of commercial negotiations; changes in the supply of and demand for crude oil, natural gas, and petroleum and petrochemical products; political or regulatory events; and other factors discussed in Item 1A of the company’s 2010 Form 10K.

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Attachment I

IMPERIAL OIL LIMITED

FOURTH QUARTER 2011

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Attachment II

IMPERIAL OIL LIMITED

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Attachment III

IMPERIAL OIL LIMITED

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Attachment IV

IMPERIAL OIL LIMITED

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Attachment V

IMPERIAL OIL LIMITED

FOURTH QUARTER 2011

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