Yes. One hardware wallet can sign for multiple multisig wallets at the same time. This is not only possible, it is extremely common in the real world.
This question usually comes from founders, advisors, or core team members who are involved in more than one project. They worry that using the same Ledger or Trezor across multiple treasuries might cause conflicts or weaken security. It does not.
Here is why.
A hardware wallet does not belong to a multisig. It does not get locked into one setup. It simply holds a private key and proves ownership of an address. Any multisig that lists that address as an owner can request a signature from it.
Multisig wallets are separate smart contracts. Platforms like Safe deploy each multisig as its own contract with its own rules, owners, and funds. Your hardware wallet is just one of the approved signers for each contract.
Think of it like being an authorized signer on multiple bank accounts. Your signature does not change depending on which account you are signing for. The account rules decide how many signatures are required, not you.
In practice, this is how many people operate. A founder might be a signer on the company treasury multisig, a DAO multisig, a foundation multisig, and maybe even a grants multisig. All of them can reference the same hardware wallet address. The wallet simply signs when approval is needed.
Security is not reduced by doing this, assuming the wallet itself is well protected. The private key never leaves the device. Each approval is explicit. Each transaction must still meet the threshold defined by that specific multisig.
What does change is responsibility. If one hardware wallet is a signer on many multisigs, losing access to that wallet affects all of them. This is why experienced teams design thresholds carefully. A 2 of 3 or 3 of 5 setup ensures that no single signer becomes a bottleneck or a single point of failure.
Another thing people worry about is confusion. Will I accidentally sign the wrong transaction for the wrong multisig? In reality, multisig interfaces are very explicit. You see the multisig address, the transaction details, and the network before you sign. Hardware wallets also show confirmation prompts, which forces you to slow down and verify.
There is also no technical limit here. One hardware wallet can be a signer on two multisigs or twenty. The blockchain does not care. It only checks whether the required number of valid signatures are present.
The important takeaway is this. Multisigs do not own wallets. Wallets approve multisigs. Once you understand that direction of control, this question stops being confusing.
Using one hardware wallet across multiple multisigs is normal, efficient, and secure when done with proper thresholds and backup plans.