Collaborative Custody Providers
Comparison of three collaborative custody approaches. All use multisig so you retain sovereign control; none can unilaterally spend your funds.
At a Glance
| Casa | Unchained Capital | Nunchuk | |
|---|---|---|---|
| Model | Subscription + concierge | Custody + financial services | Open-source mobile + advisor network |
| Multisig | 2-of-3 or 3-of-5 | 2-of-3 only | Flexible M-of-N |
| Platform | Mobile app (iOS/Android) | Web + hardware wallets | Mobile (iOS/Android) |
| Key control | You hold majority | You hold 2 keys | You hold majority |
| Recovery key | Casa holds 1 | Unchained holds 1 | Advisor holds 1 (Byzantine) |
| Bitcoin-backed loans | No | Yes | No |
| Retirement accounts | No | Yes (Bitcoin IRA) | No |
| Inheritance | Yes (legal docs) | Yes | Yes (timelocked) |
| Source code | Closed | Closed | Open source |
Casa
Subscription-based service built around proactive security and concierge support.
- Vaults: 2-of-3 (personal) or 3-of-5 (family)
- Keys: Mobile key + hardware wallet keys + one Casa recovery key
- Monitoring: Proactive alerts and key health checks
- Inheritance: Protocol with legal documentation support
Unchained Capital
Bitcoin-native financial services company with custody as the foundation.
- Structure: 2-of-3 — you hold 2 keys, Unchained holds 1
- Recovery: Cosign with their key + your remaining key if one is lost
- Products: Bitcoin-backed loans, Bitcoin IRA
- Education: Open-source tools and content
Trade-off: Financial services require KYC; narrower multisig options.
Nunchuk
Open-source mobile wallet with collaborative custody via the Byzantine advisor network.
- Model: Flexible M-of-N multisig on mobile
- Collaborative custody: Multi-user wallets where clients retain full control and an advisor holds a backup key
- Signing: Air-gapped hardware wallet support (Coldcard, etc.)
- Inheritance: Timelocked estate planning built in
- Open source: GitHub
Trade-off: No loans or IRAs; advisor network is newer and invite-based.
Decision Matrix
| If you want... | Choose |
|---|---|
| Guided mobile setup and concierge | Casa or Unchained |
| Family vault with 3-of-5 | Casa |
| Bitcoin-backed loans or retirement account | Unchained |
| Maximum key control (2 of 3 in your possession) | Unchained |
| Open-source wallet with advisor backup | Nunchuk |
| Air-gapped hardware signing | Nunchuk or Casa |
| Proactive security monitoring | Casa |
| Educational content + financial tools | Unchained |
Common Concerns
What if the company disappears? All three models are designed for this. You hold the majority of keys and can move funds without the company's involvement.
What if I lose a key?
- Casa / Unchained: Use their recovery key + your remaining keys.
- Nunchuk: Use advisor backup key + your remaining keys.
Privacy All require some KYC for the service relationship. For maximum privacy, use self-hosted multisig with Caravan or Specter Desktop.
See Also
- Casa | Unchained Capital | Nunchuk
- Custody Models — Self-custody vs collaborative custody
- Multisig — M-of-N threshold signatures
- Which Custody Model Fits My Threat Model? — Decision framework