Mr. Anthony Makuch reports

KIRKLAND LAKE GOLD ANNOUNCES UPDATED MINERAL RESERVES AT FOSTERVILLE, UNDERGROUND OUNCES MORE THAN DOUBLED, GRADE INCREASES 83%

Kirkland Lake Gold Ltd. has released the results of the company's 2017 midyear mineral reserves and mineral resources update for the Fosterville gold mine. The updated mineral reserves and mineral resources are as at June 30, 2017.

Included in the results of the mineral reserve and mineral resource update is a 110-per-cent increase in underground mineral reserves to 1.03 million ounces of gold, after depletion (processing) of 130,584 ounces, in the first six months of 2017. The main factor contributing to the significant growth in ounces is an 83-per-cent increase in the underground mineral reserve grade, to 17.9 grams per tonne gold (1.79 million tonnes) from 9.8 g/t Au (1.56 million tonnes) in the previous mineral reserve and mineral resource estimate dated Dec. 31, 2016, filed on March 30, 2017 (see press release dated March 23, 2017).

The significant increase in Fosterville mineral reserves is supported by down-plunge extensions of the high-grade, visible gold-bearing Lower Phoenix gold system. In particular, the newly named Swan zone (previously known as Lower Phoenix footwall), contributes 532,000 ounces at an average grade of 58.8 g/t Au (281,000 tonnes) to the updated mineral reserve estimate.

The increase in the mineral reserve is driven by a combination of new drill data, mining recovery improvements and a refined mineral resource estimation methodology in zones containing visible gold. The estimation methodology includes more detailed domaining and refinement of estimation parameters in areas of high-grade mineralization and is supported by an external independent review by SRK Consulting (Australasia). This work has resulted in an improvement of year-to-date mine-to-mill reconciliation.

Tony Makuch, president and chief executive officer of Kirkland Lake Gold, commented: "Fosterville is rapidly emerging as one of the world's great underground gold mines. We recently reported record quarterly production, and today are announcing that we have more than doubled underground mineral reserves, to 1.03 million ounces. The results are very encouraging as the significant growth in ounces is after deducting mine depletion to date and, in large part, reflects an 83-per-cent increase in the average underground mineral reserve grade to 17.9 g/t Au.

"The continuity of the high-grade, visible gold-bearing Lower Phoenix system is having a significant positive impact on the mineral reserve grade, production and the mine's cost profile. With the geological knowledge that we have acquired, including increased understanding of the grade distribution, we believe there is potential not only to expand these high-grade zones but to potentially find new high-grade zones along the 20 kilometres of known gold-bearing structures within our mining licence, and through exploration of the surrounding 500-square-kilometre land package.

"Within our company, we have district-scale exploration targets in prolific mining camps throughout our portfolio, through which there is considerable potential for continued growth and expansion. We remain focused on delivering superior shareholder value by targeting organic growth opportunities, supported by our aggressive 2017 exploration program, with estimated expenditures of $45[-million (U.S.)] to $55-million (U.S.). Ongoing drilling continues to enhance the geological understanding of our assets, providing confidence in the ability to delineate and expand our current mineral resource and reserve base."

Fosterville gold mine

Underground mineral reserves at Fosterville grew 110 per cent to 1.03 million ounces of gold, after depletion, accompanied by an 83-per-cent increase in grade to 17.9 g/t Au (1.79 million tonnes) from the previous estimate of 490,000 ounces of gold (1.56 million tonnes at an average grade of 9.8 g/t Au). Measured and indicated mineral resources are reported exclusive of the mineral reserves and are 1.94 million ounces of gold at an average grade of 4.4 g/t Au (13.7 million tonnes). The previous estimate at the end of 2016 was reported inclusive of mineral reserves, and included 2.79 million ounces of gold (15.3 million tonnes at an average grade of 5.7 g/t Au).

Fosterville continues to have a large underlying mineral resource base that is expected to support future additions to mineral reserves. There also remains considerable potential to further extend the current known mineral resource following continuing surface and underground drilling, which is testing near-mine gold systems up and down plunge from current mineral reserves and mineral resources. The high-grade Phoenix and Lower Phoenix gold systems, where Fosterville is currently mining, has been traced by development and drilling for over two km along trend and remains open for further expansion.

The Fosterville mineral reserves and mineral resources are provided in the associated table. Mineral resources are presented both inclusive of mineral reserves (for comparison purposes to the Dec. 31, 2016, estimates) and exclusive of mineral reserves (the approach currently being followed to be consistent with the reporting of mineral resources by the company's Canadian operations).

      FOSTERVILLE GOLD MINE MINERAL RESERVE AND RESOURCE SUMMARY AND COMPARISON, EFFECTIVE JUNE 30, 2017
  
                                                June 30, 2017                          Dec. 31, 2016                
Fosterville mine                Tonnes  Gold grade            Gold ounces    Tonnes   Gold grade  Gold ounces
                                (000s)       (g/t)                 (000s)    (000s)        (g/t)       (000s)
Mineral reserves
Underground (proven)               246        14.2                    113       280          8.4           76
Underground (probable)           1,540        18.5                    918     1,280         10.1          414
Proven plus probable             1,790        17.9                  1,030     1,560          9.8          490
CIL residues (proven)              634         7.8                    159       616          7.7          153
Total proven plus probable       2,420        15.3                  1,190     2,170          9.2          643
Mineral resources                                       inclusive of mineral reserves
Measured                         2,080         4.2                    283     2,140          4.0          274
CIL residues (measured)            634         7.8                    159       616          7.7          153
Indicated                       12,800         7.1                  2,940    12,600          5.8        2,360
Measured plus indicated         15,500         6.8                  3,380    15,300          5.7        2,790
Inferred                         5,560         5.8                  1,040     5,400          4.6          792
Mineral resources                                        exclusive of mineral reserves
Measured                         1,920         2.7                    168
CIL residues (measured)              -           -                      -
Indicated                       11,800         4.7                  1,770
Measured plus indicated         13,700         4.4                  1,940
Inferred                         5,560         5.8                  1,040

Notes
(1) CIM (Canadian Institute of Mining, Metallurgy and Petroleum) definitions (2014) were followed in 
the calculation of mineral reserves.
(2) Mineral reserves were estimated using a long-term gold price of $1,200 (U.S.) per ounce 
($1,500 (Australian) per ounce).
(3) Cut-off grades varied from two g/t Au to 3.1 g/t Au, depending upon width, mining method 
and ground conditions; dilution varying from 5 to 40 per cent and mining recovery ranging between 
60 and 100 per cent were applied to stopes within the mineral reserve estimate.
(4) Mineral reserves estimates were prepared under the supervision of Ion Hann, FAusIMM.
(5) Fosterville CIL residues are stated as proven contained ounces. Mill recoveries of 25 
per cent are planned, based on operating performance.
(6) Mineral resources were estimated using cut-off grades 0.7 g/t Au for oxide and 1.0 g/t Au 
for sulphide mineralization to potentially open-pittable depths of approximately 100 m, below 
which a cut-off grade of 3.0 g/t Au was used.
(7) Mineral resource estimates were prepared under the supervision of Troy Fuller, MAIG.
(8) Totals may not add exactly due to rounding.

Technical reports

The National Instrument 43-101-compliant 2016 technical report for Fosterville dated March 30, 2017, and effective Dec. 31, 2016, supports the company's end-of-2016 mineral reserve and mineral resource disclosure and was prepared by Mr. Fuller and Mr. Hann.

An updated NI 43-101 technical report effective June 30, 2017, to support the mid-2017 update will be available on the company's SEDAR profile within 45 days at SEDAR.

Qualified persons

Mr. Fuller and Mr. Hann are qualified persons as such term are defined in NI 43-101 and have reviewed and approved the mineral resource and mineral reserve estimates and the technical and scientific information included in this news release.

About Kirkland Lake Gold Ltd.

Kirkland Lake Gold is a mid-tier gold producer targeting 530,000 to 570,000 ounces in Tier 1 mining jurisdictions of Canada and Australia. The production profile of the company is anchored from two high-grade, low-cost operations, including the Macassa mine located in Northeastern Ontario and the Fosterville mine located in the state of Victoria, Australia. Kirkland Lake Gold's solid base of quality assets is complemented by district-scale exploration potential, supported by a strong financial position with extensive management and operational expertise.

We seek Safe Harbor.