How many departments you can create in Zoho Desk depends on your edition, and whether you can use multiple departments at all depends on your edition too.
Zoho Desk currently offers five tiers: Free, Express, Standard, Professional, and Enterprise. Free covers up to three agents with basic email ticketing. Standard removes the agent cap and adds live chat and the Answer Bot. Professional adds telephony, Zia AI, multi-department support, and light agents. Enterprise adds further capabilities including custom roles and profiles.
Departments represent the various business divisions in your organisation, and can be categorised by product line, geographical location, or team function. Each department can have its own channels, agents, business hours, and automation, letting distinct parts of your business run their support operations independently within the same Zoho Desk account.