The free plan does not expire and it is not a trial, but Raiseaticket does have Premium add-ons. Two different things can change as you grow, and it helps to keep them apart:
A free workspace covers 5 agents and 500 tickets a month, which is 6,000 a year, and it includes the core helpdesk in full: SLA policies, reports and analytics, the knowledge base, multi-factor authentication, satisfaction ratings, groups and routing, and both the email and web channels. None of that is time limited and no credit card is required.
Premium is where the integrations and branding sit:
These are separate from agent packs. Buying capacity does not switch them on, and buying Premium does not raise your agent or ticket limits.
If you pass either free limit, you can buy agent packs yourself from inside your workspace. Each pack adds 5 agents and raises both limits at once - your agent seats and your monthly ticket allowance. Add one whenever you need it; new seats are usable immediately rather than at the start of a billing period. Your tickets, history, settings and knowledge base are untouched.
Packs are billed annually and you see the price before you confirm. Add one from Settings > Subscription in your admin dashboard.
No, and this is the part people most often expect to pay for. Only agents use a seat - the people answering tickets. The User role, meaning the customers or colleagues who raise tickets and follow their own history, does not consume a seat and is not capped. You can serve as many requesters as you like without buying anything.
Only the Super Admin, who holds billing and subscription access. Administrators can manage agents, users and settings but cannot change the subscription, so routine admin work can never alter what you are charged.
Two numbers decide it: how many agents will answer tickets, and roughly how many tickets you handle in a month. If both sit inside 5 agents and 500 tickets, you need nothing at all. Your agent page shows current usage against both limits, so you can see which one you are actually approaching before deciding.