NORTHERN STAR ESTABLISHES 10-YEAR MINE LIVES AFTER RES ERVES TRIPLE TO 3.5MOZ AND RESOURCES HIT 10.2MOZ Outstanding result underpins increase in production to 600,000ozpa from next year; Reserves added at A$24/oz KEY POINTS Northern Star’s organic growth strategy has culminated in a 10.2Moz gold inventory based on Tier-1 assets in Western Australia which will underpin significant, sustainable production growth and generate industry-leading financial returns for Shareholders The substantial inventory growth stems from Northern Star’s exploration success at its Jundee and Kalgoorlie Operations, both of which have been returned to their world-class status Previously-announced guidance for FY18 stands at 525,000-575,000oz at A$1,000-A$1,050/oz; Production rate on track to reach 600,000ozpa ASX ANNOUNCEMENT in CY2018; FY19 guidance is 550,000-600,000oz 3 August 2017 Forecast expansionary capital in FY19 A$60m and FY20 A$40m (down Australian Securities from A$75m in FY17 and A$65m in FY18) Exchange Code: NST Expanded inventory and upgraded production capacity positions Jundee and Kalgoorlie Operations to each produce ~300,000ozpa Board of Directors within two years Mr Bill Beament Executive Chairman Plus, Northern Star today announces a major discovery, the Zodiac high-grade lode at Jundee; this is not included in the inventory update Mr Chris Rowe Non-Executive Director Initial assays from Zodiac show multiple mineralised intercepts over a Mr Peter O’Connor 200m single downhole interval: 4.8m at 21.2gpt, 2.9m at 10.4gpt, 0.3m Non-Executive Director at 47.0gpt, 3.6m at 4.0gpt, 3.1m at 4.3gpt & 2.5m at 5.4gpt (all true width) Mr John Fitzgerald Non-Executive Director FY2017 Reserve-Resource Update: Ms Shirley In’tVeld Non-Executive Director Total Reserves increase by 2.3Moz to 3.5Moz (despite depletion of 546,000oz in FY17) Mr David Flanagan Non-Executive Director Total Resources increase by 2.7Moz to 10.2Moz, including a 58% increase in Measured and Indicated Resources to 6.3Moz, highlighting Issued Capital mine life visibility well past current Reserves Shares 603 million Significant Reserve increases at the Tier-1 mines: Options 0.9 million Performance Rights 9.6 million ▪ Jundee up 100% to 1.45Moz (despite depletion of 259koz) Current Share Price A$4.49 ▪ Kalgoorlie Operations up 117% to 2.0Moz (despite depletion of 229koz) ▪ Kanowna up 125% to 0.6Moz Market Capitalisation A$2.7 billion ▪ NST 100% Kundana up 280% to 0.8Moz ▪ EKJV 51% Kundana up 36% to 0.6Moz Cash, Bullion & Investments 30 June 2017 - A$447.2 million Significant Resource increase at the Tier-1 mines: ▪ Jundee up 155% to 3.2Moz (now a 10Moz endowment) Projects ▪ Kalgoorlie Operations up 25% to 4.5Moz ▪ NST 100% Kundana up 52% to 1.8Moz (now larger than EKJV), Paulsens Mine Kanowna Belle Mine including a maiden Paradigm Resource of 187,000oz at 6.7gpt Kundana Mines (51% of EKJV) ▪ 51% EKJV Kundana up 35% to 1.3Moz at 6.3gpt Jundee Mine Central Tanami (25% of JV) FY18 exploration budget of A$35m to underpin Reserve replacement and potential for further growth Listed Investments VXR, DAU, RND, TBR, ALY ASX: NST Page 1 of 231 ASX ANNOUNCEMENT - 3 AUGUST 2017 Northern Star Resources Limited (ASX: NST) is pleased to announce that the Company’s three-year commitment to an organic growth strategy has culminated in substantial increases in its inventory, mine life and production profile. The outstanding result will also help underpin further growth in Northern Star’s free cash flow and ensure it retains its industry-leading financial returns. Total Reserves have increased by 2.3 million ounces to 3.5 million ounces (despite depletion of 546,000oz in FY17). The additional Reserves came at a cost of just A$24/oz. Total Resources have grown by 2.7 million ounces to 10.2 million ounces. The increased inventory will generate significant production growth, with guidance for FY19 of 550,000- 600,000oz and guidance from FY20 onwards of 575,000-625,000oz per year. This compares with previously-announced guidance for FY18 of 525,000-575,000oz. Northern Star Executive Chairman Bill Beament said the highly successful strategy had delivered the Company world-class assets as measured by several key international benchmarks. “Northern Star now has mine life visibility of 10 years,” Mr Beament said. “Our production rate will grow to 600,000oz a year or more with scope for further significant increases as we bring our Central Tanami Project on line and revitalise Paulsens through the impending exploration program there. “We will achieve this production growth while reducing our expansionary capital outlay to A$60 million in FY19 and A$40 million in FY20. This will help ensure our overall costs remain at or around current levels, positioning us for further substantial increases in free cash flow.” Mr Beament said the results of the exploration strategy at the Jundee and Kalgoorlie Operations demonstrated that they were world-class gold camps as measured by their total gold endowment, consistent Resource-Reserve replacement, annual production rates and free cash flow generation. “Our Tier-1 Jundee and Kalgoorlie Operations have the capacity to each become 300,000ozpa centres over the next two years. This would see them join an exclusive club of gold mines around the globe.” The long mine life visibility is underpinned in part by the fact that the new Resource estimate contains a 58% increase in the higher-confidence Measured and Indicated category, taking that total to 6.3 million ounces. The revised Reserve estimate includes only a small portion from several recently-defined discoveries such as Armada, Revelation, Velvet, Paradigm, Strzelecki and Raleigh South. With further work on these discoveries, Northern Star is highly confident of replacing and potentially growing Reserves again next year. The result does not include the new Zodiac discovery at Jundee, where recent drilling has intersected multiple mineralised intersections over a 200m downhole interval. Results from the discovery hole WSXP2165 include 4.8m at 21.2gpt, 2.9m at 10.4gpt, 0.3m at 47.0gpt, 3.6m at 4.0gpt, 3.1m at 4.3gpt and 2.5m at 5.4gpt (all true widths). The new Zodiac discovery is located in the Stirling fault complex some 1,000m south of the Jundee underground mine. It is hosted within the Fisher Basalt and was intersected at a depth of 1,300m in the footwall of the Jundee mine sequence. The initial Zodiac intersections span a strike length of 300m with the new mineralised corridor open in all directions beneath the Jundee mine and importantly, to the untested southern areas. Generated from a 3D seismic survey, the Zodiac discovery has the potential to significantly expand the known parameters of the world-class Jundee gold deposit. Early indications suggest it has significant potential to extend mine life further than known Reserves and Resources. ASX: NST Page 2 of 231 ASX ANNOUNCEMENT - 3 AUGUST 2017 Mineral Resource and Reserve Summary FY17 Group Mineral Reserve Estimate is 26 million tonnes at 4.2gpt Au for 3.5 million ounces. FY17 Group Mineral Resource Estimate is 92 million tonnes at 3.5gpt Au for 10.2 million ounces. These figures, which are estimated to 30 June 2017, represent JORC 2012 combined Resources and Reserves for the four assets owned by Northern Star. ORE RESERVES As at 30 June 2017 PROVED PROBABLE TOTAL RESERVES Tonnes Grade Ounces Tonnes Grade Ounces Tonnes Grade Ounces NST ATTRIBUTABLE (000's) (gpt) (000's) (000's) (gpt) (000's) (000's) (gpt) (000's) TOTAL 4,607 4.4 646 21,355 4.2 2,861 25,962 4.2 3,506 MINERAL RESOURCES As at 30 June 2017 MEASURED INDICATED INFERRED TOTAL RESOURCES Tonnes Grade Ounces Tonnes Grade Ounces Tonnes Grade Ounces Tonnes Grade Ounces NST ATTRIBUTABLE (000's) (gpt) (000's) (000's) (gpt) (000's) (000's) (gpt) (000's) (000's) (gpt) (000's) TOTAL 7,051 4.3 975 41,167 4.0 5,352 43,732 2.8 3,902 91,949 3.5 10,229 A full breakdown of each Project’s Reserves and Resources can be found in Appendix A. Over the past three years since the acquisition of Northern Star’s Tier-1 portfolio, A$150 million has been spent in exploration to grow Resources, Reserves and mine lives. During this period, Northern Star has added 4.0Moz in Reserves at a cost of A$37/oz and 7.1Moz of Resources at a cost of A$21/oz. These significant additions show the quality of the multi-million ounce endowments that the Company operates in and their ability to continue yielding substantial quantities of gold (refer to graph below). NST Resource and Reserve Growth 12.0 5.0 10.2 Mozs 4.5 10.0 4.0 3.5 Mozs 3.5 7.5 Mozs 8.0 7.3 Mozs 3.0 6.0 2.5 4.7 Mozs 1.75 Mozs 2.0 Ozs M Reserve Resource M OzsResource 4.0 1.3 Mozs 1.5 1.1 Mozs 2.2 Mozs 1.0 2.0 1.4 Mozs 0.9 Mozs 0.5 0.2 Mozs MY 10 MY 11 MY 12 MY 13 MY 14 MY 15 MY 16 MY 17 Measured + Indicated Inferred Reserves Resources ASX: NST Page 3 of 231 ASX ANNOUNCEMENT - 3 AUGUST 2017 Forecasted Group Gold Production The Jundee and Kalgoorlie Operations have the capacity to each become 300,000ozpa centres over the next two years. This achievement will enable Group production to grow to 600,000oz a year.