Exhibit 99.1 Leading Provider of Sustainable Future Materials 2022 Earnings Release 2023. 1. 27.

Disclaimer This presentation was prepared and circulated to release the informations regarding the company’s business performance to shareholders and investors prior to the completion of auditing for the period of fiscal year 2022. As figures in this presentation are based on unaudited financial statements, certain contents may be subject to modification in the course of auditing process. This presentation contains certain forward-looking statements relating to the business, financial performance and results of the company and/or the industry in which it operates. The forward-looking statements set forth herein concern future circumstances and results and other statements that not historical facts, and are solely opinions and forecasts which are uncertain and subject to risks. Therefore, the recipients of this presentation shall be aware of that the forward-looking statements set forth herein may not correspond to the actual business performance of the company due to changes and risks in business environments and conditions. The sole purpose of this presentation is to assist persons in deciding whether they wish to proceed with certain investments to the company. The company does not make any representation or warranty, expressly or impliedly, as to the accuracy and completeness of this presentation or of the information contained herein and shall not have any liability for the informations contained in this presentation. 4Q22 Earnings Release │ January 27, 2023 2

Contents Consolidated Business Performance Major Business Activities Business Performance by Major Areas 2023 Business Outlook Appendix 4Q22 Earnings Release │ January 27, 2023 3

Consolidated Business Performance Green infrastructure · Green materials businesses showed growth, while steel profit weakened due to the flood and slow demand YoY Financial Structure Income 84,750 12.8 9.5% (billion KRW) 76,332 (trillion KRW) 8.7% YoY Net Debt Ratio △4.3 8.5 Revenue 57,793 12.1% +8,418 6.5% 6.0 EBITDA 5.7% 4.2% △6.4%p 9,238 OP Margin +2.0 5.6 9,238 4.1 △4,388 Operating 4,850 3.6 Net Debt 2,403 Profit 2020 2021 2022 2020 2021 2022 【Before Inter-company Transaction Adjustment】 Revenue Operating Profit (billion KRW) 2021 2022 2021 2022 4Q YoY 4Q YoY Steel +3,913 66,737 15,112 70,650 8,440△718 3,236△5,203 * POSCO 39,920 8,675 42,695 +2,775 6,650 623 2,295△4,355 △ Overseas Steel 21,712 5,487 23,933 +2,221 1,474 166 474△1,000 △ Green Infrastructure 54,104 14,885 65,901 +11,797 1,214 235 1,544 +330 POSCO International 33,949 7,967 37,990 +4,041 585 169 903 +318 POSCO Energy 1,976 1,151 3,707 +1,731 203 40 271 +68 POSCO E&C 8,199 2,571 9,435 +1,236 441 22 309△132 Green Materials 2,089 808 3,389 +1,300 113 7 144 +31 △ POSCO Chemical 1,990 781 3,302 +1,312 122 3 166 +44 ＊POSCO Parent result before the vertical spin-off is included 4Q22 Earnings Release │ January 27, 2023 4

Major Business Activities_Expansion of Future Growth Businesses Secured long-term growth engines for Green materials·energysector and put continuous efforts to improve business structure under a holding company in 2022 3.23 4.12 6.28 10.11 10.31 11.10 3.2 11.4 3.29 6.22 8.26 10.14 12. Steel/Non-Steel CAPEX Steel/Non-Steel OP Trend (tril KRW) 5.0 60% (tril KRW) Steel Steel 3.6 4.0 60% Non-Steel 50% 50% Non-Steel 48% 3.0 4.0 50% 3.2 Non-Steel Ratio Non-Steel Ratio 3.0 35% 40% 40% 3.0 45% 32% 29% 26% 30% 2.0 30% 1.7 2.0 1.3 20% 20% 20% 20% 1.0 1.0 14% 10% 10% 0.0 0% - 0% 2018 2019 2020 2021 2022 2018 2019 2020 2021 2022 (%) 2018 2019 2020 2021 2022 (tril KRW) 2018 2019 2020 2021 2022 Non-Steel Revenue 43.4 43.2 39.7 56.3 69.4 Net Debt Ratio 20.4 16.6 8.7 6.5 9.5 * P-Holdings' revenue(dividend income) and OP were eliminated from Non-Steel’s 4Q22 Earnings Release │ January 27, 2023 5

Full restoration from the flood damage Completed the restoration of Pohang Steel Works on Jan. 20, and reinforced its disaster prevention system Recovery Progress Prevention of Recurrence ○ System : Established BCP(Business Continuity Planning) ○ Completed the restoration of all 17 steel-processing facilities and started normal operations at Pohang Works - Reinforced comprehensive anti-disaster measures in dealing with situations of typhoon/earthquake/fire, etc. - No.1 Plate line was shut down due to production efficiency - Improved counterplans and manuals of response actions, not only for (Production capacity : 600k tons) natural disasters but major accidents including fire/explosion/collapse. ○ Material : Supplemented infrastructure to avoid the flood, etc. ~Dec. 2022 Jan. 2023 No.1 No.2 No.3 No.2 Wire Rod PlateWire Rod Wire Rod Hot Impact (Nov14)(Nov25) (Dec14) (Oct20) Rolling ü Operating loss 1,340 bil KRW No.1 No..3 No.4 No.2 Line HR Plate Wire Rod HR (bil KRW) 3Q22 4Q22 2022 (10/7) (10/24) (Nov29) (Dec15) POSCO 408 857 1,265 Impact on 222 568 790 No.3 No.1 production/sales decline* Electrical Electrical No.1 Inventory loss 94 1 95 No.1 No.2 Steel Steel STSCR Repair, material cost 92 288 380 CR CR Cold (Sep15) (Dec30) (Jan20) (Oct6) (Dec12) Subsidiaries 27 47 74 Rolling Total 436 904 1,340 No.2 Electrical No.2 CGL * Based on IFRS, increased amount of fixed cost caused by temporary production drop Line Electrical Galvanizing Line STSCR (Jan20) was realized 3Q and 4Q COGS Steel (Nov11) (Dec24) (Sep28) ü Non-OP loss 236 bil KRW : impairment loss on tangible assets ※ Receipt of insurance on 4Q22 : 234 bil KRW 4Q22 Earnings Release │ January 27, 2023 6

Completed construction of PLSC, POSCO HY Clean Metal Started commercial production of cathode materials by recycling with construction completion of PLSC · POSCO HY Clean Metal [Upstream] PLSC* * Poland Legnica Sourcing Center ○ Outline ○ Outline - Business model : extracting cathode materials such as lithium, - Business model : crushing secondary battery scrap and providing nickel, cobalt, etc. using black mass black mass** to POSCO HY Clean Metal - Location : LiB materials Complex of Gwangyang, Korea - Location : Brzeg Dolny, Poland - Processing cap. : black mass 12k tons/yr - Processing cap. : secondary battery scrap 10k tons/yr - Production cap. : 7 products including nickel 2.5k tons/yr, cobalt - Production cap. : black mass 8k tons/yr 0.8k tons/yr, lithium carbonate 2.5k tons/yr - Revenue cap. : 70 bil KRW in 2023 (forecast) - Revenue cap. : 110 bil KRW in 2023/ 300 bil KRW in 2024 (forecast) ○ Schedule○ Schedule Dec.22 May.23 Sep.23 Feb.23 Dec.23 Aug.22 Dec.22 Jan.23 May.23 Certification Complete Acquire business Start Commercial Acquire Normal Normal Start Commercial construction license production production business license Capacity Capacity construction production 【 PLSC plant (completed) 】 【 POSCO HY Clean Metal plant (completed)】 Site for expansion PLSC No.1 plant 2 2 (110 thousand m ) (60 thousand m ) ** Black Mass : Black powder obtained by crushing and selectively collecting lithium-ion battery scrap(lithium, nickel, etc.) 4Q22 Earnings Release │ January 27, 2023 7

Mid-to Long-term Strategies of Recycling Business Expand global supply chain of materials through localization by region, in connection with POSCO Chemical’s cathode business ○ Build the ‘Closed Loop’ of ‘scrap→cathode’ by recycling business associated with cathode orders - Secondary battery manufacturers and OEMs prefer ‘Closed Loop’ supply chain due to increasing restrictions on the quantity used of recycled raw materials ○ Review to establish plants in North America and EU, in order to satisfy needs for supply chain localization of secondary battery materials - In preparation for U.S. IRA* , EU CBAM/Digital Battery Passport, localization is necessary ü By 2030, secure recycling production cap. of nickel 30k tons, lithium carbonate 30k tons, cobalt 5k tons 【Mandatory usage rate of recycled 【Candidates by region】 raw materials in EU** 】 20% 20% '30년 '35년 15% 12% 12% 10% HUB (Finland) 10% HUB (Poland) HUB (Canada) 4% 4% HUB (Tennessee) 5% HUB HUB (California) (Gwangyang) 0% 리튬니켈코발트 * IRA : Inflation Reduction Act ** Source : EU Batteries Regulation(under consideration) 4Q22 Earnings Release │ January 27, 2023 8

[Downstream] POSCO HY Clean Metal [Upstream] PLSC Technology Development for LiB Recycling Developing next-generation pyrometallurgical technology by combining POSCO’s smelting technology with currently existed production process Current Process ○ Background ○ Process Highlights - Currently, workers manually dismantle packs and modules 1. Highest level of Ni, Co recovery rate in the industry which makes difficult to process large volume of end of 2. Li recovery rate : minimum 85% (battery-grade) life batteries(EoLB) with safety concerns 3. Reducing No. of workers by production automation - With own capability, POSCO is developing pyrometallurgy (Refining, 60% of Chinese companies) technology for mass EoLB treatment ○ Process Highlights ○ Process Flow 1. Automated pre-treatment process for mass production without Black mass Scrap/EoLB dismantling and discharging 2. High-purity NCM* alloy and Li compound production by high Dismantling Graphite Acid Leaching temperature heat treatment ᆞdischarging Impurity 3. Simplified process compared to conventional hydrometallurgy Shredding Removal reduces CAPEX and increases Li recovery rate Cu Copper Solvent ○ Process Flow Heat treatment Electrowinning Extraction Scrap/EoLB NCM Alloy Li Compound Mn, Co, Ni Copper metal Milling Automated Solvent Crystallization Acid Leaching Heat treatment Pre-treatment Extraction Separation Impurity Mn Sulfate Shredding Refining Sodium Removal Crystallization Sulfate Black mass High Temp Co Sulfate Cu Cu Solvent Dry/Milling Heat treatment Electrowinning Extraction Crude LC Li precipitation Ni Sulfate Lithium NCM** Graphite Separation Cu metal Solution Carbonate Refining Lithium Li Compound NCM Alloy Dry/Milling Carbonate * Nickel, Cobalt, Manganese, Copper alloy ** Nickel, Cobalt, Manganese liquid 4Q22 Earnings Release │ January 27, 2023 9

Integrated corporation of P-International and P-Energy Create synergy through integration of value chain in energy sector → Strengthen the group’s business portfolio Statutory merger of P-International(remaining company) to buy P-Energy(extinguished company), Outline the integrated corporation officially launched on Jan.1, 2023 • After merger, POSCO Holding’s stake of POSCO International will be increased from 62.9% to 70.7% After merger Before merger Market Market Newshares capitalization capitalization Issuedshares123,375,149 Issuedshares45,194,806 IssuedShares175,922,788 52,547,639 2.8 tril KRW 3.9 tril KRW (P-Holdings 62.9%) (P-Holdings 89.0%) (P-Holdings 70.7%) rd Invest 3.8 tril KRW by 2025, and become the group’s 3 growth engine by completion of LNG value chain Objective and transition to Green energy business Investment Strategies Mid-to long-term targets by 2030 LNG Value Chain (2023~2025 , t ri lKRW) U [Natural gas reserves] • Secure new explorations of LNG(by 2024), and 57Bcf/yr P E&P 1.3 1.6 Tcf → 2.5 Tcf system from Senex/0.4 mil tons of LNG in Korea(by 2025) M • Establish more terminals*and expandbunkering/test [LNG Sales·LNG Storage cap.] I operation of LNG carrier/trading LNG Infra. 0.3 mil tons → 12 mil tons D 1.6 *complete cons truction of No.6by2024, No.7,8by2025, Dangjin No.1,2by 2026 0.7 mil ㎘ → 3 mil ㎘ D • Establish New No.3, 4 units(1GW, apply blending hydrogen, start O [Power generation cap.] P o w er Gen er a t io n cons truction on 2024), start Gas-to-Power ** business overseas W 0.7 3.6GW → 7.6GW N (1.4GW by 2025) [Renewable energy cap.] • Develop renewable energy business such as Jeonnam Offshore Eco- f r i e ndl y E ne r g y 0.2 0.1GW → 2.4GW Wind Power Complex(es ta blish SPC by 2023, acquire licenseby 2023),and installation of solar panel on the roof ofP-Chemical(2.2MW) 4Q22 Earnings Release │ January 27, 2023 10 *BCF Billion cubic feet, TCF: Trillion cubic feet **Gas to Power : a package of businesses from LNG procurement to power plant construction/operation

Business Performance by Major Areas Steel - POSCO · Production/Sales · Income/Financial Structure - Overseas Steel · PT-KP · PZSS · P-Maharashtra · PY-VINA Green Infrastructure - POSCO International - POSCO Energy - POSCO E&C Green Materials - POSCO Chemical 4Q22 Earnings Release │ January 27, 2023 11

POSCO_Production/Sales Production Sales YoY * Utilization Rate 88.3% 94.1% 84.1%△10.0%p (thousand tons, %) YoY 35,456 38,264 Sales Volume (thousand tons) 34,270 35,935 Crude Steel △3,312 59.1 32,144 Domestic 34,219△4,045 56.3 △2.8%p Sales Ratio 35,801 55.4 34,437 Product △3,528 WTP 32.5 32,273 Sales Ratio* 28.6 △3.9%p 26.7 2020 2021 2022 2020 2021 2022 * Utilization rate : Crude Steel Production / Crude Steel Capacity *Un-ordered and semi-product figure excluded in total sales volume ○ Sales volume shrunk in 2H 2022 as production volume ○ Crude steel and product production volume decreased decrease due to slow demand and the flood damage due to the flood damage, Gwangyang No.4 BF repair and on rolling lines in Pohang Works Pohang No.1 BF shutdown • Softened the impact of sales volume decrease by maximizing • Pohang) No.1 BF shutdown(Dec.29, 2021), the flood(Sep.6, 2022) production of Gwangyang Works and sales of slab • Gwangyang) No.4 BF repair (Feb.11~Jun.10, 2022, 119 days) 【Sales volume by quarter】 (k tons) 2022 1Q 2Q 3Q 4Q YoY 【Carbon Steel/STS Production Volume】 (k tons) CR/Coated 2,081 1,917 2,039 1,818 7,855△497 1Q22 2Q22 3Q22 4Q22 Plate 1,308 1,392 1,220 971 4,891△663 QoQ HR 2,099 2,068 2,035 2,260 8,462△638 Carbon Steel 7,930 7,886 7,552 7,428△124 STS 494 453 352 186 1,487△496 Products Sales Volume 8,454 8,239 7,904 7,547 32,144△3,312 STS 455 348 151△197 523 ※ WTP 2,468 2,232 2,200 1,782 8,682△2,343 ※ Sales of Slab 95 112 144 706 1,057 +393 * 1Q22 : Included POSCO Parent result before the vertical spin-off * 1Q22 : Included POSCO Parent result before the vertical spin-off 4Q22 Earnings Release │ January 27, 2023 12

POSCO_Income/Financial Structure Income 【Operating Profit YoY】 YoY (billion KRW) (billion KRW) +2,775 42,695 △8,526 39,920 6,650 Revenue△1,330 16.7% 6,766 △475 Production 26,510 OP Margin /Sales 5.4% Repair cost △11.3%p 6,650 Volume△790 and losses 4.3% Drop, etc. from ASP Raw material Production 2,295 the flood increase Input cost △4,355 2,295 /sales increase Operating decrease by 1,135 the flood Profit 2021 2022 2020 2021 2022 • Raw Material Input Cost : Coking Coal 234, Iron ore 95 * 2020, 2021 : POSCO Parent result before the vertical spin-off (2021 average price = 100) (billion KRW) 2020 2021 2022 YoY - Coking coal price hiked up due to global imbalance by the Ukraine war, etc. EBITDA 3,516 9,047 4,673△4,374 * Raw Material Input Cost of 4Q22 : Coking Coal 80, Iron ore 96 (3Q22 average price = 100) ○ OP dropped as margin reduced by slow demand in 2H 2022 • Sales Price(carbon steel, thousand KRW/ton) : 2021) 975→2022) 1,147 (+172) and one-off cost including repair cost, while revenue went up due - Decreased in 2H 2022 due to slow demand and drop in exchange rates to sales price increase ※ Price trend(thousand KRW/ton) : (1Q) 1,136 – (2Q) 1,236 – (3Q) 1,186 – (4Q) 1,025 ○ Cash balance increased, net debt decreased • Recognized one-off cost due to the flood damage by 475 bil KRW At the - Repair cost : 380 bil KRW(material cost, maintenance cost, etc.) (trillion KRW) ’22.E spin-off(’22.3.1) - Inventory impairment loss : 95 bil KRW(finished/semi-product, materials, etc.) Cash Balance 5.5 7.6 • Impacted by 790 bil KRW due to shutdown from the flood damage Debt 7.1 7.8 - Impacted by decreased fixed cost and sales volume due to the production decline 4Q22 Earnings Release │ January 27, 2023 13

Overseas Steel Subsidiaries_Performance Turned to losses as of 4Q due to slow global steel demand in 2H 2022 PT. Krakatau POSCO Zhangjiagang STS (PZSS) • Sales volume and profit dropped year-on-year due to raw material • Recorded profit loss as shrunk margin due to the Chinese Zero cost increase and slow steel demand in 2H 2022 COVID-19 policy, while STS raw material costs stayed at high level - Increased in coking coal input cost by 107% year-on-year by the Ukraine war and demand increase of nickel for battery 2,355 - Price of LME Ni(U$/ton) : 2021) 18,488 → 2022) 25,605 (+7,117) △27 2,328 3,275 3,275 - Revenue 2,575 Revenue 1,433 503 221 Operating Operating △282 128 △187 14 Profit Profit (USD million) (USD million) △58 △59 YoY YoY 2020 2021 2022 2020 2021 2022 POSCO Maharashtra PY VINA • Profit faltered while revenue went up due to increased costs of • Profit decreased as sales volume and price dropped due to loan materials and raw materials restrictions of the Vietnamese government, weak construction - Increased in sales price by 2% , purchase price of materials by 13% year-on-year market, and excessive inventories of distribution centers +12 1,479 - Sales volume of section products(k tons) : 2021) 433 → 2022) 400 (△33) 1,467 414 357 △57 Revenue Revenue 274 748 180 35 Operating Operating 20 39 △141 5△30 Profit Profit (USD million) (USD million) △10 2020 2021 2022 2020 2021 2022 YoY YoY 4Q22 Earnings Release │ January 27, 2023 14

POSCO International_Performance Major Activities Income YoY 37,990 (billion KRW) ○ Trading +4,041 33,949 - Steel : Recorded the highest revenue as of POSCO products Revenue sales over 10 million tons 21,472 • Sales volume of POSCO products(million tons) : 2021) 9.4 → 2022) 10.3 - Agriculture : Showed sharp decrease of crop sales volume 903 +318 due to the Ukraine war, while profits from palm biz. enlarged Operating 585 475 Profit • Crop sales volume(million tons) : 2021) 6.6 → 2022) 3.6 2.4% +0.7%p 2.2% 1.7% • Operating Profit of palm business(bil KRW) : 2021) 76 → 2022) 102 OP Margin ○ Energy ’20년 ’21년 ’22년 - Myanmar gas field : Revenue/profit improved due to rise in sales price and exchange rates 【Revenue by Business】 3 • Gas sales volume(bil ft ) : 2021) 195 → 2022) 189 • Operating profit(bil KRW) : 2021) 181 → 2022) 350 (bil KRW) 2020 2021 2022 YoY - Senex Energy : M&A in 2022→ target to triple the production Trading volume by 2025 19,298 32,470 36,377 +3,907 3 • Sales volume of Senex Energy(bil ft ) : 2022) 17 Energy 2,174 1,479 1,613 +134 • Acquired in Apr. 2022 : P-international’s stake 50.1% for 405 bil KRW • Apr.~Dec. 2022: Revenue 187, OP 39 bil KRW(OP Margin 20.8%) * Other sales of earnings from real estate including Songdo Tower excluded 4Q22 Earnings Release │ January 27, 2023 15

POSCO Energy_Performance Major Activities Income YoY 3,707 +1,731 (billion KRW) ○ Power Generation : Operating profit went up due to electricity demand increase and sales price impact 000 Revenue • The end of social distancing and a revival of industries lead 1,976 electricity demand increase • SMP increased as LNG price went up 1,517 【Market Index】 271 Operating +68 2020 2021 2022 YoY Profit 241 Power demand(GW) 72 75 78 +3 203 OP Margin SMP(KRW/kWh) 16% 68 94 196 +102 10%△3%p 7% ○ Terminal : Operating profit went up due to stable tank 2020 2021 2022 rental services and expansion of connecting businesses 【Revenue by Business】 • Generated stable profit from tank rental services to SK, S-Oil, etc. • Increased profit from LNG sales by expanding sales of the export (bil KRW) 2020 2021 2022 and import businesses utilizing its own tanks YoY • Profitability recovered by expanding commissioning business of Power Generation 1,278 1,698 3,274 +1,576 LPG vessels(1→7, +6 vessels), despite of profit decrease in LNG ship commissioning from LNG price hike Terminal 143 178 316 +138 • Gwangyang No.6 LNG Tank construction underway(target to be completed by May 2024) Fuel Cell, etc. 96 100 117 +17 4Q22 Earnings Release │ January 27, 2023 16

POSCO E&C_Performance Major Activities Income (billion KRW) YoY ○ Operating Profit decreased due to construction materials price hike, while revenue increased Revenue • Plant : Profit increased year-on-year(+35 bil KRW) due to new 9,435 +1,236 construction PJT and profit improvement of overseas PJT, etc. 8,199 7,794 • Infrastructure : Profit increased year-on-year(+13 bil KRW) by speeding up processes of PJT and winning a suit of indirect Operating costs, etc. 441 Profit 380△132 5.4% 309 • Construction : Profit rapidly dropped year-on-year(△187 bil KRW) 4.9% 3.3% OP Margin due to revenue decrease and additional costs from increases in △2.1%p materials cost/outside order expenses, etc. ○ Orders slightly decreased year-on-year, while city 2020 2021 2022 housing projects increased (Total order in 2022 : 10.8 tril KRW,△0.4 tril KRW YoY) 【Revenue by Business】 • Plant(3.2 tril KRW, △0.2YoY) : Orders of chemical plant increased (bil KRW) 2020 2021 2022 YoY * Dangjin LNG Terminal(0.4), Kumho ethylene rubber plant(0.2), etc. Plant 1,722 1,839 2,535 +696 • Infrastructure(0.7 tril KRW, △0.1YoY): Groundwork for Dangjin LNG Terminal(0.1), etc. Infrastructure 798 841 1,354 +513 • Construction(6.9 tril KRW, △0.1YoY) : increased orders of city Building 4,748 4,339 4,235△104 housing projects(41%→54%) Consolidated 526 1,180 1,311 +131 * Jeongneung renewal project(0.6), Changwon remodeling(0.5), etc. subsidiaries 4Q22 Earnings Release │ January 27, 2023 17

POSCO Chemical_Performance Major Activities Income ○ Cathode : Both revenue and profit increased, (billion KRW) YoY 3,302 profitability improved +1,312 • Sales volume increased(+40%) due to maximizing production/ Revenue 1,990 sales of N65 and having ZPHE on a consolidated basis 1,566 • Revenue went up by 156% due to increase in sales volume and 166 raw materials price, and rise in exchange rates ※ Exchange rate 1,144 à 1,292KRW/USD(yoy+13%) 122 +44※ Lithium price +409%, Nickel price +150% 6.1% Operating 5.0% • Profitability recovered due to increase in utilization rate and Profit 60 △1.1%p rise in sales price linking with the raw material price 3.8% OP Margin○ Anode : Profitability slightly weakened despite of revenue increase • Showed sluggish sales volume increase due to slow demand 2020 2021 2022 by the shortage of semiconductor materials for EV, and increasing 【Revenue by Business】 uses of Chinese • Profitability recovered from 2H 2022 as sales price increased in (bil KRW) 2020 2021 2022 accordance with raw material(graphite) price increase YoY ○ Refractories, Quicklime/Chemical : Profitability dampened Cathode materials 351 678 1,722 +1,044 • Refractories : production volume decreased due to the flood and Anode materials 182 174 216 +42 recognized repairing expenses • Chemical : profit declined due to sales price differences generated Refractories 453 463 565 +102 from the oil price drop Quicklime/Chemical 580 675 799 +124 • P&O Chemical : Recorded loss because of initial fixed cost after its construction completion(June) 4Q22 Earnings Release │ January 27, 2023 18

2023 Business Outlook Consolidated Revenue 86 (trillion KRW) CAPEX 11 (trillion KRW) Net Debt 11 (trillion KRW) 4Q22 Earnings Release │ January 27, 2023 19

Appendix 2022 POSCO Safety Management Activities Summarized Income Statement Summarized Balance Sheet 4Q22 Earnings Release │ January 27, 2023 20

2022 POSCO Safety Management Activities Established safety-first culture and secured practical safety management system Established practical and strong health and safety management system §【Budget】 Strengthened safety control by creating a process for pre-executing the safety budget Safety §【System】 Run Safety Management Committee and Group’s Safety Council, Advisory Council for Safety, and acquired System evaluations from outside agency §【Affiliates】 Reinforced safety control by developing a health and safety platform combining affiliate companies ＊ Total Recordable Injury Frequency Rate Transferred core value from production-oriented to safety-first ＊ § Settled ‘Field First’ culture by management-led, operated TRIFR indicator Safety § Established the Joint Labor-Management Committee/Safety report center, routinized to improve against hazardous risks Culture § Focused on compliance with Rule & Process : operated process indicators including Safety rule compliance index, etc., and application of safety accidents ＊ Process Safety Management ＊ Provided safety education by visiting affiliated companies Secured workforce and competency for leading the system/culture Safety ＊ §【Workforce reinforcement】 Safety manager(16→83) and PSM instructor(107→191) Workforce ＊ §【Infrastructure fortification】 Lifeguard(328→567), Safety Bus (2→4) and Shelter(51) Serious Accidents Decreased ＊Completed compensation process for the past serious accidents Source : Worldsteel No. of seriously injured employees : 1 Pohang) No.3 Cokes line accident(Jan. 20) 5 0.030 No. of seriously ＊ FFR injured employees 0.013 1 1 ＊ Fatality Frequency Rate 2020 2021 2022 POSCO(2022) Worldsteel(2021) 4Q22 Earnings Release │ January 27, 2023 21

Summarized F/S_Consolidated Income Statement (billion KRW) 2020 2021 2022 1Q 2Q 3Q 4Q YoY Revenue 57,793 76,332 84,750 21,338 23,010 21,155 19,247 8,418 Gross Profit 4,720 11,881 7,649 2,929 2,733 1,608 379 4,232 △ (Gross margin) (8.2%) (15.6%) (9.0%) (13.7%) (11.9%) (7.6%) (2.0%) ( 6.6%) △ SG&A 2,317 2,643 2,799 671 635 688 805 156 Operating Profit 2,403 9,238 4,850 2,258 2,098 920 425 4,388 △△ (Operating margin) (4.2%) (12.1%) (5.7%) (10.6) (9.1) (4.3) ( 2.2) ( 6.4%) △△ Net Profit 1,788 7,196 3,560 1,907 1,799 592 737 3,635 △△ EBITDA 6,010 12,806 8,544 3,146 3,007 1,847 543 4,249 △ (EBITDA Margin) (10.4%) (16.8%) (10.1%) (14.7%) (13.1%) (8.7%) (2.8%) 6.7% △ EPS (KRW) 20,165 87,330 46,988 25,187 23,717 7,800 9,716 40,342 △△ No. of outstanding shares 79,121 75,696 75,815 75,710 75,849 75,849 75,849 119 (thousands) 4Q22 Earnings Release │ January 27, 2023 22

Summarized F/S_Consolidated Balance Sheet (billion KRW) 2020 2021 2022 YoY Current Assets 35,831 46,622 47,650 1,028 Cash & Cash Equivalents 16,365 18,156 18,739 583 Accounts Receivable 8,121 10,062 9,770 292 △ Inventories 9,052 15,215 15,472 257 Non-Current Assets 43,256 44,850 50,757 5,907 Tangible Assets 29,400 29,597 31,781 2,184 Intangible Assets 4,449 4,166 4,839 673 Other LT Financial Assets 1,562 2,120 2,333 213 Total Assets 79,087 91,472 98,407 6,935 Liabilities 31,412 36,667 40,149 3,482 Current Liabilities 16,855 21,084 23,188 2,104 Non-Current Liabilities 14,557 15,583 16,961 1,378 Total Debt 20,498 21,741 24,306 2,565 ※ Shareholders’ Equity 47,675 54,805 58,258 3,453 Owners of the Controlling Stake 44,331 50,427 52,520 2,093 Net Debt 4,133 3,590 5,554 1,964 Net Debt to Equity (%) 8.7% 6.5% 9.5% 3.0% 4Q22 Earnings Release │ January 27, 2023 23