• The Fedimint Model: Fedimint vs Samourai for Privacy-Preserving Bitcoin
  • What Fedimint Actually Is
  • How Samourai Differs
  • The Trust Model Comparison
  • The Key Insight: They Stack
  • Key Takeaways

§The Fedimint Model: Fedimint vs Samourai for Privacy-Preserving Bitcoin

Two approaches to privacy-preserving Bitcoin custody have emerged as the most technically serious: Fedimint (federated Chaumian mint) and Samourai-style (single-user self-custody with advanced privacy tools). Understanding what each actually does matters for anyone serious about Bitcoin privacy.

§What Fedimint Actually Is

A Fedimint is a federation of guardians who collectively custody Bitcoin for users. Your Bitcoin is split into shares held by multiple guardians — no single guardian can access your funds. To spend, you need signatures from a threshold of guardians (typically 2-of-3 or 3-of-5).

The mint aspect: users deposit Bitcoin and receive “e-cash tokens” — cryptographic promises from the federation that can be redeemed for Bitcoin on-chain. These tokens are bearer instruments: whoever holds them can redeem them. Privacy comes from the federation accepting deposits without KYC and issuing tokens that aren’t linked to on-chain addresses.

§How Samourai Differs

Samourai is a single-user self-custody wallet with advanced privacy tools: CoinJoin (Whirlpool), PayJoin, and Stonewall. You never give up control of your keys. Privacy comes from breaking the transaction graph through collaborative transactions and sophisticated heuristics that make chain analysis much harder.

The tradeoff: Samourain’s privacy is limited by the privacy of your counterparty in any transaction. If you CoinJoin with one party who is later identified, the analysis can work backward. Fedimint’s privacy is limited by the federation’s operational security — if guardians collude or get hacked, funds are at risk.

§The Trust Model Comparison

Fedimint: you trust the federation. Specifically:

• A threshold of guardians must collude to steal your funds
• Guardians must not be coerced by governments (the federation can be compelled to freeze)
• The federation’s Bitcoin holdings are identifiable on-chain (even if user transactions aren’t)

Samourai: you trust no one but yourself. Privacy comes from cryptographic techniques, not trust. But: your privacy depends on transaction counterparty behavior, and certain tools (Stonewall, PayJoin) require willing counterparties.

§The Key Insight: They Stack

The most sophisticated users run both: Samourai for personal custody with aggressive privacy-tool usage for day-to-day transactions, and a Fedimint membership for larger holdings where the federation’s custodian model provides additional separation from on-chain identity.

These approaches aren’t competing — they serve different threat models.

§Key Takeaways

• Fedimint: federated guardianship, threshold security, Chaumian e-cash tokens for privacy
• Samourai: self-custody with cryptographic privacy tools (CoinJoin, PayJoin)
• Fedimint’s privacy depends on federation trust; Samourain’s depends on cryptographic techniques
• Both are legitimate approaches for different threat models
• The best privacy strategy stacks multiple approaches

⚡ If this was useful, a zap is always welcome. tomford@rizful.com