All paid plans include wildcard domains and the number of domains by plan are as follows:
Free: 1 domain
Launch: 2 domains
Scale: 3 domains
Optimize: 3 domains
Can I add more domains without upgrading?
Additional domains can be added as a paid add-on. Contact Unlayer support or your account manager to confirm the options for your plan and arrange the addition.
Do I need a separate entry for every subdomain?
A wildcard entry such as *.yourdomain.com covers subdomains such as app.yourdomain.com and staging.yourdomain.com under a single domain entry.
See How and where should I add my allowed domain(s)? for configuration guidance.