Each adult needs a separate account, as each individual must complete certain forms (like USPS 1583).
In order to add a family member to your account, the original account holder will be asked during their onboarding to enter the family member's email address. From there, the family member will receive an invitation email. They simply need to log into the SavvyNomad customer portal and complete their own onboarding (including an initial notary session).
For your spouse, we can attach a 50% discount in perpetuity to their account (if you have the basic plan) or a 100% discount if you have the middle-tier or higher plan. However, for your spouse, they will still need to add a payment method on file in case they request a mail item forwarded (for postage) or if they use the online notary.