Solo Mining vs Pool Mining: When Solo Makes Sense
Pool mining is the default for almost every operator: you join a pool, you get steady predictable payouts, and you avoid the brutal variance of solo mining. But solo Bitcoin mining isn’t dead — it’s a real choice for specific operators with specific tolerance profiles. This guide explains the math behind both, when solo actually makes sense, and which solo miner hardware fits each scenario.
For specific hardware recommendations covering Bitaxe, Avalon Nano 3S, and full-size rigs configured for solo mode, see our Best Solo Bitcoin Miner 2026 guide.
The variance problem
Bitcoin mining is a probabilistic process. Each block has a probability of being found by your hardware equal to your share of network hash rate. With an Antminer S21 XP at 270 TH/s on a 700 EH/s network, your share is ~0.0000004 — meaning every block, you have a 1-in-2.6-million chance of finding it.
Over enough blocks, the law of large numbers smooths your returns toward the expected value. But the time horizon matters:
| Hardware | Expected solo block frequency | Realistic outcome over 1 year |
|---|---|---|
| S21 XP (270 TH/s) | ~50 years per block | Almost certainly zero blocks found |
| 10× S21 XP (2.7 PH/s) | ~5 years per block | Maybe 1 block; could be 0 or 2 |
| 100× S21 XP (27 PH/s) | ~6 months per block | 1–4 blocks expected, high variance |
| 1000× S21 XP (270 PH/s) | ~3 weeks per block | 15–25 blocks, manageable variance |
For a single-rig operator, solo mining is essentially a lottery. You might hit a block in your first year (and earn 3.125 BTC + fees, $200,000+ at 2026 prices); you might run for 30 years and never hit one. Most operators can’t tolerate that variance, so they pool.
How pool mining works
A pool aggregates hash rate from thousands of miners and submits the combined work to the network. When the pool finds a block, it distributes the reward proportionally to participants based on their contributed work.
Key effect: variance compresses dramatically. Daily payouts become predictable rather than lottery-style. The cost is a small pool fee (1–2.5% typical) and a marginal increase in trust assumption (the pool operator could theoretically misbehave).
For practical pool selection, see our mining pools guide. Foundry, AntPool, F2Pool, ViaBTC, and Braiins are the mainstream choices.
When solo mining makes sense
Three real scenarios:
1. Lottery-style hobbyist
A single rig running solo has expected payouts of zero per year. But conditional on finding a block, the payout is ~$200,000 (block reward + fees at 2026 prices). For operators willing to treat the expected value as ~zero and the conditional jackpot as a fun upside, solo mining is a reasonable hobby.
This works mathematically only if you’d be running the rig anyway (e.g., for heat reuse — see our heat source guide) and the lottery-ticket value is a bonus rather than a target.
2. Network-decentralization motivation
Pool concentration is a long-running concern. Three pools control over 60% of Bitcoin hash rate. Each rig that mines solo (rather than joining a top-3 pool) marginally increases network decentralization. For operators who care about Bitcoin’s long-term health beyond their own returns, solo is a small but real contribution.
Practically: Bitcoin Core has built-in solo-mining support via the “block template” interface. Some hardware (Bitaxe, NerdMiner) ships with solo mining as a default config option for this reason.
3. Very large fleet operators
At ~1000+ S21 XPs (27 EH/s, ~4% of network), variance becomes manageable enough that solo mining produces stable returns. The 1–2% pool fee saved becomes meaningful in absolute dollars at this scale.
Practical: only the largest mining companies (Marathon, Riot, Core Scientific, Foundry-affiliates) operate at this scale. They typically run hybrid setups — most hash to a pool for predictability, some hash solo for fee savings and decentralization signaling.
The math of “lottery solo”
Suppose you run an S21 XP at 270 TH/s, 3,645 W, $0.06/kWh power. Solo mining:
- Daily power cost: $5.25
- Expected daily revenue: $9.85 (same as pool, before fees)
- Variance: typically zero days yield revenue; a “win” day yields ~$200,000
- Annual expected value: $1,672 net (same as pool minus pool fees, plus saved 1–2%)
- Annual realistic outcome: -$1,917 (no block found, pure power costs) with 2% chance of +$197,917 (block found)
The expected value math is identical to pool mining. The difference is variance. Most operators value variance reduction substantially — that’s why pools dominate.
Hybrid: P2Pool and Stratum V2
Two technical innovations that change the trade-off:
P2Pool
A peer-to-peer mining pool — no central operator, just miners running pool software that coordinates among themselves. Lower fees (typically 0%), no centralization concern, but operationally more complex. Hash rate participation is small (~1% of network); not suitable for serious commercial operations.
Stratum V2
The next-generation mining protocol that moves block template construction from the pool to the miner. Practical effect: pools no longer choose which transactions to include in blocks — miners do. Doesn’t change the variance economics but addresses the censorship-resistance concern around pool concentration. Adoption is still rolling out across pools and hardware.
The honest summary
Solo mining is for two operators: hobbyists treating it as a lottery, and very-large-scale operators where variance is naturally compressed. For everyone in between, pool mining is the right answer.
If you do decide to solo mine, set realistic expectations: zero revenue most days, with a small chance of a block win that’s life-changing. Don’t size your hardware purchase around a solo-mining cashflow scenario; you’ll never hit the expected value.
For pool selection: mining pools guide. For setup: setup guide. For overall first-miner decisions: decision tree.