All-In Sustaining Cost (Mining)
All-In Sustaining Cost (AISC) is a standardized cost metric developed by the World Gold Council that captures the full per-ounce cost of sustaining gold (or silver) production at an existing mine, including direct mining costs, overhead, sustaining capital expenditures, and corporate expenses, enabling meaningful cost comparisons across gold mining companies.
Before AISC was introduced in 2013, gold mining companies reported a wide variety of cost metrics — cash costs, total cash costs, total production costs — with inconsistent definitions that made cross-company cost comparisons unreliable. The World Gold Council developed AISC to create a single comprehensive measure of the true cost of maintaining current production levels, helping investors and analysts evaluate which mining companies produce gold most efficiently.
AISC includes direct mining costs (labor, energy, reagents, consumables), royalties, by-product credits, sustaining capital expenditures (capital spending required to maintain existing mine output at current levels, distinct from growth capital), exploration costs needed to maintain the reserve base, and allocated corporate general and administrative expenses. It excludes growth capital for new mines or expansions, as well as non-cash items like depletion and amortization.
Formula: AISC ($/oz) = (Operating Costs + Sustaining Capex + Corporate G&A + Exploration Costs - By-product Credits) / Ounces Produced
For gold producers listed in the United States, AISC is a key differentiator. Companies like Newmont Corporation (NEM) — the largest gold miner in the world — and Barrick Gold (GOLD), a major producer with U.S.-listed shares, report AISC quarterly and provide full-year guidance on AISC ranges. The spread between the gold price and AISC defines the gross margin per ounce and thus the profitability of the business at any given gold price level.
A company with AISC of $1,100 per ounce produces gold at a comfortable margin when gold trades at $1,900, but faces profitability pressure if gold falls to $1,200. Lower-cost producers with AISC below $1,000 per ounce enjoy substantial margins across a wider range of gold prices, while higher-cost producers are more vulnerable to commodity price downturns.
Investors use AISC to calculate the margin per ounce, compare cost structures across peer companies, and assess what gold price environment each producer needs to remain profitable. AISC is also used in mine valuation models to project future profitability under different commodity price scenarios. While the World Gold Council definition has brought substantial standardization, some variation remains across companies in how they classify sustaining versus growth capital, so investors should review company-specific definitions when making detailed comparisons.