Can I add a co-owner after opening a Time Deposit?

Yes, a primary owner can invite a co-owner while the Time Deposit is active, if the option is available in the Salmon app. They can do this even if the Time Deposit has already been funded or is close to maturity.

The invited person must accept the invitation and complete all required steps before the account matures.

After the Time Deposit matures and closes, the primary owner cannot add a co-owner anymore. To save together again, you can open a new Time Deposit and invite co-owners again.