Exhibit 99.1

Calgary, July 26, 2012

Imperial Oil announces estimated second quarter financial and operating results

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

Imperial Oil’s earnings in the second quarter of 2012 were $635 million, compared with $726 million in the second quarter of 2011. Earnings were lower primarily due to lower crude oil realizations and higher planned maintenance activities. These factors were partially offset by stronger industry refining margins compared to 2011. Our Chemical segment continued to perform very well with record quarterly earnings of $49 million.

In our Upstream business, significant planned downtimes were completed at Cold Lake and Syncrude. Both downtimes were essentially on time and on budget but did result in less production versus the same time period last year.

Our Downstream business continued to contribute solid earnings despite significant refinery maintenance activities, which impacted our second quarter results by $120 million. Substantial planned maintenance at our Strathcona and Nanticoke refineries along with unplanned downtime at Sarnia reduced our ability to fully capitalize on strong mid-continent refining margins.

Capital and exploration activities to the end of June were $2,481 million and were directed to company growth projects at Kearl and Cold Lake. Our continued strong business performance allowed us to finance these investments largely by cash flow from operations. We are pleased with our workforce’s ability to sustain base business performance while executing a complex portfolio of capital projects. The Kearl initial development remains on track to start-up by the end of the year.

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Second quarter highlights

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Second quarter 2012 vs. second quarter 2011

The company’s net income for the second quarter of 2012 was $635 million or $0.75 a share on a diluted basis, compared with $726 million or $0.85 a share for the same period last year.

Lower second quarter earnings were primarily attributable to the impacts of lower upstream realizations due to lower commodity prices of about $345 million and higher planned maintenance events totalling about $230 million, which included about $120 million at the Downstream refineries and about $110 million at Syncrude. Earnings in the second quarter of 2012 were also impacted by higher Kearl production readiness expenditures of about $30 million. These factors were partially offset by the impacts of stronger industry refining margins of about $270 million, lower royalty costs of about $145 million and a weaker Canadian dollar of about $50 million. Second quarter earnings in 2012 included a gain of about $25 million from the sale of assets.

Upstream net income in the second quarter was $360 million versus $624 million in the same period of 2011. Earnings decreased primarily due to lower realizations of about $345 million, lower Syncrude volumes due to planned maintenance activities of about $75 million and higher Syncrude maintenance costs of about $35 million. Earnings in the second quarter of 2012 were also impacted by higher Kearl production readiness expenditures of about $30 million. These factors were partially offset by lower royalty costs due to lower realizations of about $145 million and the impact of a weaker Canadian dollar of about $50 million. Second quarter earnings in 2012 included a gain of about $25 million from the sale of assets.

Prices for most of the company’s liquids production are based on West Texas Intermediate (WTI) crude oil, a common benchmark for mid-continent North American oil markets. Compared to the corresponding period last year, the average WTI crude price in U.S. dollars was lower by $8.99 a barrel or nine percent in the second quarter of 2012. Also, discounts for bitumen and synthetic crude oils increased in the second quarter, reflecting high industry refining downtime in mid-continent North America. For the second quarter, bitumen realizations in Canadian dollars decreased 17 percent and synthetic crude oil realizations in Canadian dollars decreased 19 percent compared to the corresponding period last year.

Gross production of Cold Lake bitumen averaged 152 thousand barrels a day during the second quarter, versus 158 thousand barrels in the same period last year. Lower volumes were primarily due to planned maintenance activities at the Mahkeses plant as well as the cyclic nature of production at Cold Lake.

The company’s share of Syncrude’s gross production in the second quarter was 60 thousand barrels a day, versus 70 thousand barrels in the second quarter of 2011. Planned maintenance of one of the three cokers in the second quarter was the main contributor to lower production in the period.

Gross production of conventional crude oil averaged 20 thousand barrels a day in the second quarter, up from 16 thousand barrels in the corresponding period in 2011 when third-party pipeline downtime significantly reduced production at the Norman Wells field.

Gross production of natural gas during the second quarter of 2012 was 195 million cubic feet a day, down from 257 million cubic feet in the same period last year. The lower production volume was primarily a result of the impact of divested producing properties.

Downstream net income was $232 million in the second quarter, $168 million higher than the second quarter of 2011. Earnings increased primarily due to the favourable impact of stronger industry refining margins of about $270 million. This factor was partially offset by the unfavourable impact of significant maintenance activities of about $120 million.

Industry refining margins continued to be strong in the second quarter, as the overall cost of crude oil processed at three of the company’s four refineries followed the trend of WTI prices and Western Canadian crude oils. Canadian wholesale prices of refined products are largely determined by wholesale

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Second quarter 2012 vs. second quarter 2011 (continued)

prices in adjacent U.S. regions, where wholesale prices are predominately tied to international product markets. Stronger industry refining margins are the result of the widened differential between product prices and cost of crude oil processed. Substantial planned maintenance activities at Strathcona and Nanticoke refineries along with unplanned downtime at the Sarnia refinery reduced our ability to fully capitalize on the strong refining margins.

Chemical net income was $49 million in the second quarter, the best quarter on record and $13 million higher than the same quarter last year. Stronger operating performance along with higher polyethylene sales volumes and margins were the main contributors to the increase.

Net income effects from Corporate and other were negative $6 million in the second quarter, in line with $2 million in the same period of 2011.

Cash flow generated from operating activities was $1,317 million in the second quarter, an increase of $661 million from the corresponding period in 2011. Higher cash flow was primarily due to working capital effects.

Investing activities used net cash of $1,224 million in the second quarter, compared with $893 million in the same period of 2011. Additions to property, plant and equipment were $1,290 million in the second quarter, compared with $903 million during the same quarter 2011. Expenditures during the quarter were primarily directed towards the advancement of Kearl initial development and expansion. Other investments included advancing the Nabiye expansion project at Cold Lake, environmental and efficiency projects at Syncrude, as well as tight oil acreage acquisitions.

The company’s cash balance was $996 million at June 30, 2012, down $206 million from $1,202 million at the end of 2011.

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Six months highlights

Six months 2012 vs. six months 2011

Net income for the first six months of 2012 was $1,650 million or $1.94 a share on a diluted basis, versus $1,507 million or $1.76 a share for the first half of 2011.

For the six months, earnings increased primarily due to stronger industry refining margins of about $410 million and lower royalty costs of about $95 million. These factors were partially offset by lower upstream realizations of about $245 million due to lower commodity prices and lower Syncrude volumes of about $105 million, due primarily to increased planned maintenance impacts.

Upstream net income for the six months of 2012 was $902 million versus $1,152 million from 2011. Earnings were lower primarily due to the impacts of lower realizations of about $245 million, lower Syncrude volumes of about $105 million and higher maintenance costs of about $45 million. These factors were partially offset by lower royalty costs of about $95 million and the impact of a weaker Canadian dollar of about $60 million.

Prices for most of the company’s liquids production are based on West Texas Intermediate (WTI) crude oil, a common benchmark for mid-continent North American oil markets. Compared to the corresponding period last year, the average WTI crude price in U.S. dollars was lower by $0.35 a barrel or less than one percent in the first six months of 2012. Also, discounts for bitumen and synthetic crude oils increased in the first six months of 2012, reflecting high industry refining downtime in mid-continent North America. For the first six months of 2012, bitumen realizations in Canadian dollars, decreased one percent and synthetic crude oil realizations in Canadian dollars decreased seven percent compared to the corresponding period last year.

Gross production of Cold Lake bitumen was 155 thousand barrels a day this year, compared with 157 thousand barrels in the same period of 2011. Slightly lower volumes were primarily due to planned maintenance activities at the Mahkeses plant as well as the cyclic nature of production at Cold Lake.

During the six months of the year, the company’s share of gross production from Syncrude averaged 67 thousand barrels a day, down from 75 thousand barrels in 2011. Planned maintenance activities on one of the three cokers in the second quarter were the main contributor to lower production in the period.

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Six months 2012 vs. Six months 2011 (continued)

Gross production of conventional crude oil averaged 20 thousand barrels a day in the first six months of the year, up from 19 thousand barrels in the corresponding period in 2011 when third-party pipeline downtime significantly reduced production at the Norman Wells field.

Gross production of natural gas during the six months of 2012 was 197 million cubic feet a day, down from 263 million cubic feet in the six months of 2011. The lower production volume was primarily a result of the impact of divested producing properties.

Downstream net income was $687 million, an increase of $347 million over 2011. Higher earnings were primarily due to stronger industry refining margins of about $410 million. This factor was partially offset by the unfavourable impact of a higher level of refinery planned maintenance activities compared with 2011 totalling about $80 million.

Chemical net income was $84 million, up $10 million from 2011. Earnings were positively impacted by improved margins across all product channels and higher polyethylene sales volumes.

For the six months of 2012, net income effects from Corporate and other were negative $23 million, versus negative $59 million last year due to lower 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 2011 Form 10K.

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Attachment I

IMPERIAL OIL LIMITED

SECOND QUARTER 2012

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Attachment II

IMPERIAL OIL LIMITED

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(a) Cash flows from operating activities was higher in the second quarter of 2012 when compared to the same period in 2011 primarily due to working capital effects.

Cash flows from operating activities was higher in the first six months of 2012 when compared to the same period in 2011 primarily due to working capital effects and the timing of scheduled income tax payments.

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Attachment III

IMPERIAL OIL LIMITED

SECOND QUARTER 2012

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Attachment IV

IMPERIAL OIL LIMITED

SECOND QUARTER 2012

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Attachment V

IMPERIAL OIL LIMITED

SECOND QUARTER 2012

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