Core Scientific and IREN expect to end bitcoin mining by December 31, 2026; contracts price them from January
Core Scientific and IREN both set December 31, 2026, as mining's end in the same day's earnings. From January their equities price on contracted power, credit and construction instead of the coin.
Richard Tang · 3 min read
Core Scientific+0.88% — Core Scientific, up 0.88 percent today, one of the largest listed bitcoin miners, and IREN+21.46% — IREN, up 21.46 percent today, the Australian-founded miner building AI-cloud capacity for Microsoft−0.14% — Microsoft, down 0.14 percent today, both set December 31, 2026, as mining's end in earnings materials dated November 5 134. "We expect to complete our exit from Bitcoin mining by year end," Core Scientific chief executive Adam Sullivan said on the call, and IREN's quarterly filing expects its transition substantially complete by the same date, with immaterial mining through 2027 23.
Core Scientific's filed release is softer, repurposing facilities only "as circumstances allow," so the date rests on management's word 9. The switch is the right one: a megawatt serving AI tenants earns several times what mining pays 4.
A megawatt earns several times more serving models
Producing a coin now costs public miners more than the coin fetches 41. One analyst estimate puts a megawatt's five-year mining yield near $1.9 million, against roughly four times that from AI data-center workloads 4. What is left is thin: Core Scientific's self-mining ran a gross loss last quarter 2, and IREN's mining revenue fell 88% in a year as rigs are pulled out to make room for GPUs 3.
Core Scientific's revenue bottomed with mining in 2025, then doubled as colocation filled
Data
| Revenue | |
|---|---|
| Q3 '24 | $95.35M |
| Q4 '24 | $94.93M |
| Q1 '25 | $79.53M |
| Q2 '25 | $78.63M |
| Q3 '25 | $81.1M |
| Q4 '25 | $79.76M |
| Q1 '26 | $115.24M |
| Q2 '26 | $164.2M |
AI tenants already dwarf mining at both exiting miners
Mining is a single-digit share of revenue at both companies switching it off
- AI revenue (colocation / AI cloud)
- Bitcoin mining and hosting
Data
| AI revenue (colocation / AI cloud) | Bitcoin mining and hosting | |
|---|---|---|
| Core Scientific | $215.4M | $17.5M |
| IREN | $200M | $28M |
The halls are rebuilt as contracts, not closed
The sites are repurposed rather than sold. Power, cooling and floor space become high-density colocation, rented under take-or-pay leases that pay whether or not the tenant uses the capacity 9. Core Scientific carries more than $24 billion of contracted revenue across CoreWeave+3.96% — CoreWeave, up 3.96 percent today and an AMD+10.28% — AMD, up 10.28 percent today-backed block 5; IREN's backlog tops $20 billion, two-thirds of it with investment-grade customers 6. Holders who bought these stocks as an AI landlord plus a bitcoin call keep only the landlord from January.
The coin leg of the trade is being switched off with the rigs.
Riot and Hut 8 mine while they build
The other camp converts without a shutdown date. Riot signed a $28 billion Corsicana lease with the AI lab Anthropic$350B — Anthropic, private, latest valuation $350B and is selling its mined bitcoin to fund the build; mining at that site could begin winding down only in summer 2027 7. Hut 8+5.52% — Hut 8, up 5.52 percent today still earns nearly all its revenue from mining and compute while its AI leases pay little until halls open in 2027, and MARA holds the largest coin treasury among public miners 8.
The bottleneck is now the balance sheet, not the coin
With the coin gone, what prices these equities is construction and financing. Core Scientific spent close to $1 billion last quarter adding billable megawatts, a bill we have tracked since shareholders refused CoreWeave's $9 billion bid; IREN trimmed this year's build plan because capital markets turned selective; both stocks fell hard in this week's AI-infrastructure selloff 9613. The reward now belongs to whoever finishes the halls and starts billing megawatts, because the conversion, not the coin, is where the value gets created.
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