Subaccounts in the Casa app allow you to have multiple multisig vaults within a single Casa account. Subaccounts allow you to keep your your funds separated in different pools.
Subaccounts are currently supported for bitcoin (BTC) only.
Why would I use subaccounts?
While having a subaccount in the Casa app is optional, there are several reasons why you may want to have an additional wallet:
- You're HODLing for different goals or different people, and want to track these balances individually
- You've earned some of your coins pseudonymously (e.g., from mining), and don't want to mix them with coins you've bought on an exchange
How do I create a subaccount?
We'll use the 3-key vault as an example here, but the same process applies with a 5-key vault. Since you'll be using the same keys for your subaccount as you use for your primary multisig vault (you won't be adding additional keys for this new wallet), you'll first need to create your primary 3-key vault.
Once your 3-key vault for BTC is set up (or if it's set up already), you would first tap the vault you want to create a subaccount for, then tap the "+" button in your vault view.
Next, tap "continue" to create the subaccount. You can name your subaccount now if you want, but you can always come back and change the name later on.
Example subaccount creation flow for a BTC vault
Your subaccount is now ready to deposit funds!
How do I send from my subaccount?
Subaccounts are secured using the same keys as your primary vault. Therefore, when you need to send funds from your subaccount vault, you would send just as you normally would. You will still need to apply multiple signatures to the transaction in order for funds to be sent from any multisig vault.
How many subaccounts can I have?
How many subaccounts you can have depends on your Casa membership level.
- Standard members have access to their 3-key vault, plus one subaccount vault (two total)
- Premium members and Private Clients have access to their 5-key vault, plus four subaccount vaults (five total)
Can I hide subaccounts if I'm not using them?
Yes, you can hide unused subaccounts in the Account tab of your Casa app settings. By toggling "Show Deactivated Subaccounts," you can either show or hide the inactive subaccount vault(s). (Note: This item will not display in the Account tab if you do not have any deactivated subaccounts.)
Can I use subaccounts to manage funds held in my IRA?
We recommend checking with your tax professional first as this can have tax implications. Casa is unable to provide tax advice.
To be safe, our guidance is to store your personal funds and any funds in your IRA in fully separate Casa accounts and to avoid using any personal funds (e.g., a personal credit card) to pay for your IRA membership.
How do subaccounts work technically?
When you create a BTC vault in the Casa app, Casa imports the root extended public keys ("root xpubs") for each device (Trezor, Ledger, mobile key, etc.). The Casa app uses these to create new receive addresses every time you make a deposit.
When you create a subaccount, Casa derives an unused set of child extended public keys ("child xpubs") from each of these root xpubs following the BIP 32 standard. All the receive addresses in the new subaccount will be created from this set of child xpubs. If you create a second subaccount, yet another set of child xpubs will be derived from the root xpubs and all addresses in that subaccount will be derived only from that second set of child xpubs.
The bottom line is that even though your subaccounts are all managed by the same keys, they are each based upon distinct sets of xpubs and the resulting addresses create no data on the blockchain that can be used by an observer to correlate funds in the different subaccounts, as long as you don’t send funds from one subaccount to another.
