Calendar

Every command and flag is in the proton calendar reference. This page is the things people actually do.

See what’s on

proton calendar events list
proton calendar events list --calendar Work --start 2026-04-15 --end 2026-04-30
proton calendar events get "Team sync"

Every calendar is included unless --calendar narrows it. --start and --end are the first and last whole days to include, read in your own zone; without them you get the next 30 days.

An event is on a day when it touches any part of it, so a query for one day inside a three-day event returns it. A recurring event is listed on each day it happens, with a reference naming that occurrence:

$ proton calendar events list --start 2026-04-20 --end 2026-04-27
ID                         DATE        TIME     DURATION  TITLE           LOCATION
─────────────────────────  ──────────  ───────  ────────  ──────────────  ────────
4f2a1b9c@2026-04-20T09:00  2026-04-20  09:00    15m       Standup         Meet
7bd3e011                   2026-04-21  all day  1d        Public holiday
4f2a1b9c@2026-04-22T10:30  2026-04-22  10:30    30m       Standup (long)  Meet
4f2a1b9c@2026-04-27T09:00  2026-04-27  09:00    15m       Standup         Meet

Create an event

proton calendar events create --title Dentist --start 2026-04-16T14:00 --duration 1h
proton calendar events create --title Conference --start 2026-04-20 --all-day --duration 3d
proton calendar events create --calendar Work --title "Quarterly sync" \
  --start 2026-04-16T14:00 --duration 90m --location "Vienna HQ" --description "Numbers and roadmap"

How long an event lasts is said once, with either --end or --duration. Both together is refused, and so is either without --start.

Flag	Accepts
--start	2026-04-16T14:00, 2026-04-16 14:00, 2026-04-16, or full RFC 3339
--duration	15m, 90m, 1h, 2h30m - or 3d for an all-day event
--remind	15m, 1h, 1d, repeatable; add :email for an emailed one
--start / --end on list	YYYY-MM-DD, both days included
--zone	an IANA zone name, e.g. Europe/Vienna

--all-day makes an event with no time of day, measured in days. It ends at the midnight after its last day, which is how every other calendar client writes it.

--status says whether the event is going ahead: confirmed, tentative or cancelled. Cancelling this way keeps the event and its history, which delete does not.

Attendees. Proton users are added directly; external addresses get an emailed invitation. A bare address is required; --attendee jane@example.com:optional is not.

Recurrence. --rrule takes an iCal recurrence rule. Pair it with --zone: a series anchored to Europe/Vienna stays at 09:00 when the clocks change, where one stored as a plain UTC instant would slide to 08:00.

proton calendar events create --title Standup --start 2026-04-16T09:00 --duration 15m \
  --rrule "FREQ=WEEKLY;COUNT=10" --remind 15m --zone Europe/Vienna

Change or answer one

proton calendar events update REF --title "New title" --start 2026-04-17T10:00 --duration 2h
proton calendar events respond "Team sync" --answer accept     # emails the organizer
proton calendar events delete "Dentist"

Anything you do not mention is left alone, including the reminders, the recurrence and the occurrences you have cancelled. --answer is accept, tentative or decline, and applies to the whole invitation rather than to one occurrence.

Recurring events, occurrence by occurrence

The reference decides how far a change reaches. Keep the @occurrence part and you act on that occurrence; drop it and you act on the series. --future widens one occurrence to it and everything after.

# move one standup, leaving the series alone
proton calendar events update 4f2a1b9c@2026-04-22T09:00 --start 2026-04-22T10:30 --duration 30m

# cancel one standup
proton calendar events delete 4f2a1b9c@2026-04-22T09:00

# from May the 4th on, it moves half an hour later
proton calendar events update 4f2a1b9c@2026-05-04T09:00 --start 2026-05-04T09:30 --future

# end the series there
proton calendar events delete 4f2a1b9c@2026-05-04T09:00 --future

# the whole series
proton calendar events delete 4f2a1b9c

Deleting a series removes every occurrence, so it says how many and shows them first. --future on the first occurrence is refused, because nothing would be left - delete the series instead.

Reminders

events list shows which triggers an event carries. reminders list answers the other question - when they go off:

$ proton calendar reminders list --start 2026-08-27 --end 2026-08-28
ID                         FIRES             REMIND  TITLE    STARTS              LOCATION
─────────────────────────  ────────────────  ──────  ───────  ──────────────────  ────────
7bd3e011                   2026-08-27 06:00  6h      Piano    2026-08-27 all day
4f2a1b9c@2026-08-27T09:00  2026-08-28 08:45  15m     Standup  2026-08-28 09:00    Room 3

A reminder is listed on the day it fires, not the day its event is on: an event with two triggers is two rows, and a recurring one is a row per occurrence. An all-day event’s reminder goes off at the calendar’s chosen morning hour whatever trigger produced it. Emailed reminders are Proton’s to send and are left out.

The same rows, live:

proton calendar reminders watch --output json | jq -c .

watch sleeps until the moment rather than polling, so a line lands on the second, and it re-reads your calendars as it goes so an event added meanwhile still reminds you. The last column is the sentence a notification would say (says in JSON). See Desktop notifications.

Import and export

proton calendar events export --start 2026-01-01 --end 2026-12-31 --output year.ics
proton calendar events import holidays.ics
curl -s https://example.com/team.ics | proton calendar events import -

A recurring series is exported once with its rule rather than expanded, so another client reads it back as the same series. Reminders travel as VALARM components. An event that cannot be decrypted is left out rather than written as a stub.

An import is addressed by UID. An event carries the UID of the event it is, so reading a file back changes that event rather than making a second one: export, edit, import, and the calendar says what the file says. The replacement is a new event with a new ID, so a reference held from before no longer resolves. --dry-run lists what the file holds first.

Participants are left out. An imported event is a record, not an invitation being reissued, and writing the guests back would make your account the organizer of a meeting it did not call - which for external addresses means email going out.

Your calendars

proton calendar settings calendars create --name Work --color "#8080FF"
proton calendar settings calendars update Work --default-duration 30m --remind 15m
proton calendar settings calendars update Personal --busy off
proton calendar settings calendars delete Work

Each calendar carries its own defaults for the events made in it. --busy says whether events there make you look busy to people checking your availability; --no-remind gives new events none.

Colours have to be Proton accent colours. Deleting a calendar asks for your password even though you are signed in - Proton guards that endpoint behind an elevated session. With no terminal, pass --password-file or --password-stdin.

Subscribing to a published calendar

proton calendar settings calendars create --name Timetable --url https://example.com/team.ics

Proton fetches the .ics on a schedule and fills the calendar from it, so the events are read-only - they belong to whoever publishes them. A listing says which calendars are which under KIND. Proton is asked whether it can read the address before the calendar is made, so a wrong one is refused rather than leaving you with a calendar that never fills.

Sharing

proton calendar settings calendars share add Work jane@proton.me --edit
proton calendar settings calendars share list Work
proton calendar settings calendars share remove Work jane@proton.me

A calendar is opened by a passphrase, and every member holds that passphrase encrypted to their own key. So sharing is not a permission Proton grants - it is handing somebody the key, encrypted so only they can read it and signed so they can tell it came from you. That is why it only works with another Proton account: an address Proton holds no keys for has nothing to encrypt to.

They see nothing until they accept, and until then share list shows them as pending. share remove withdraws an unanswered invitation or ends a membership.

For a calendar somebody gave you:

proton calendar invitations list
proton calendar invitations accept Work

Until you accept you see the calendar’s name and who sent it, and nothing that is on it.

Settings

proton calendar settings          # time zones, layout, invitations
proton calendar settings set view week
proton calendar settings set primary-timezone Europe/Vienna

Key	Values
view	day, week, month, year, planning
week-numbers · auto-detect-timezone · show-secondary-timezone · auto-import-invite	off, on
primary-timezone · secondary-timezone	an IANA zone
invite-locale	a language, e.g. en_US
default-calendar	a calendar ID