What it is
Calendar is free. Calendar Pro is an optional one-off upgrade from the Microsoft Store - no subscription and no account. Everything Pro adds is listed under Calendar Pro in the left sidebar (click it to open the list), and Pro features carry a PRO badge until you have it. You can try it all free for 7 days first: no payment details, and it switches off by itself.
Reminders
Edit an event and pick a time in the Reminder field (from 1 week before to the start time). Windows shows a notification at that time, even when Calendar is closed. All-day events and milestones remind you from the start of your working day.
Printable Planners
··· → Print & export → Printable planner. Choose a day page, week, month or a 12-month year wall planner; the Classic, Minimal or Site board style; A4, A3 or Letter; and whether to include your events, notes, UK bank holidays and ruled lines. Print it, or choose Microsoft Print to PDF to save it.
Project Report
Choose Project Report in the ··· menu (top right) and pick a project: every event tagged to it, planned against logged hours, how many are completed, and Export CSV for a timesheet or invoice backup.
On-device AI assistant
AI diary entry in Day view, Weekly update (AI) in the ··· menu, an AI summary in the Project Report, and ✨ next to an event's title to tidy it. It runs entirely on your PC - nothing is sent anywhere - and never changes anything until you click Copy, Append or Use this title.
Themes Pack
Six extra themes in Settings → Theme: Midnight, Graphite, Forest and Plum (dark), Paper and Ocean (light).
More Linked Calendars
One linked Outlook, Google or Apple calendar is free. With Pro you can link as many as you like.
Year View
Click Year at the top (or press 6). All twelve months, with a dot for each day's events in their colours and UK bank holidays shaded. Click a day to open it, or a month's name for Month view. Print year planner opens the year wall planner.
Calendar Subscriptions
+ Add calendar → Bank holidays & more in the sidebar: bank holidays for Scotland, Northern Ireland and England and Wales (from GOV.UK, with one-off holidays), Irish public holidays and the UK clock changes. They show like linked calendars, read-only, and you can remove them at any time.