Import CSV Calendar to Outlook: Steps, Limits, and Fixes

Yes. In classic Outlook for Microsoft 365 on Windows, go to File > Open & Export > Import/Export, choose Import from another program or file, then Comma Separated Values, and select your CSV. Choose the Calendar folder and map the CSV columns to Outlook fields before finishing. The direct CSV import is a classic Outlook feature; in new Outlook, Outlook on the web, and Outlook for Mac, you will generally need to convert the data to an iCalendar file (.ics) first.

What CSV calendar import does—and does not do

A CSV, or comma-separated values file, is a table of text: each row can represent one event and each column an event property such as its subject, date, time, location, or description. It is a useful format when a booking system, spreadsheet, or other service provides calendar data as a table. Outlook’s classic Windows import wizard can turn those rows into appointments in a chosen calendar.

Importing is a one-time copy, not a live connection. If the source spreadsheet changes later, Outlook does not automatically update the imported events. Nor does importing a CSV subscribe Outlook to the original calendar. You can import the revised file again, but that can create duplicate appointments unless you manage the existing items or choose the appropriate duplicate option in the wizard.

A CSV also has limits compared with a calendar-specific format. It is well suited to separate dated events, but it does not reliably convey every calendar feature, such as complex recurrence rules, meeting invitations, attendee responses, or all timezone details. If those matter, ask the source for an .ics file or another Outlook-compatible calendar export.

Prepare the CSV before importing

Check the file in a spreadsheet or text editor before opening Outlook. The first row should contain clear column headings, and each event should have its own row. A practical layout might include Subject, Start Date, Start Time, End Date, End Time, Location, and Description. Outlook may use different field names in its mapping list, so the headings do not have to match perfectly; mapping is what connects a source column to an Outlook field.

Make sure every event has a meaningful subject and a start date. Include an end date and end time where appropriate, especially for appointments that last longer than a day or have a defined finish. For an all-day event, use a dedicated all-day column if your source provides one, and check how its values are represented. A row with an end time of midnight can be interpreted differently from an all-day event, so do not rely on that as a substitute.

Use consistent date values, such as 11/18/2026 throughout the file, rather than mixing formats such as 11/18/2026 and 18/11/2026.
Keep start and end times in separate columns if the export provides them. Check that the times are actual time values or consistently formatted text.
Review commas, line breaks, and quotation marks in descriptions. A correctly formed CSV encloses text containing commas in quotation marks; avoid manually editing delimiters unless you know the file structure.
Save a working copy of the original file. If dates or text look wrong after import, you can correct the source and repeat the process.

Date interpretation can depend on Windows regional settings and the format used by the exporting system. For example, 04/05/2026 could mean April 5 or May 4. If the source can export unambiguous dates, use that option; otherwise, verify a few rows before importing a large calendar.

Import a CSV in classic Outlook for Windows

These steps apply to classic Outlook for Microsoft 365 on Windows, not the newer Outlook app. If the interface has a simplified layout and no File tab with the classic commands, you may be using new Outlook.

Open classic Outlook and select File > Open & Export > Import/Export.
In the Import and Export Wizard, select Import from another program or file, then select Next.
Select Comma Separated Values and select Next. Browse to the CSV file you prepared.
Choose how Outlook should handle duplicate items: replace duplicates, allow duplicates, or do not import duplicates. If you are unsure, avoid allowing duplicates on a repeat import.
Select the destination Calendar folder. If Outlook has multiple accounts or calendars, confirm that you are choosing the calendar where the events should appear.
Select Map Custom Fields if the wizard offers it. Match the CSV columns to the Outlook fields, then confirm the mapping.
Select Finish and allow Outlook to complete the import. Open the destination calendar and inspect the dates, times, and event details.

Menu wording can vary slightly between Outlook builds, but the important distinction is to choose the Calendar folder as the destination, not the Contacts or Tasks folder. If you import into a shared mailbox or another account, you may also need permission to add or edit items there.

Map columns and check a sample event

The mapping step is where you tell Outlook what each column means. A source heading called Event Name, for example, should map to Subject; a column called Venue should map to Location. Common Outlook fields include Subject, Start Date, Start Time, End Date, End Time, Location, and Body. The Body field is typically where a longer description belongs.

Do not map a column just because its name looks similar. A source column named Created On might describe when the record was entered into the source system, not when the calendar event starts. Map it to Start Date only if it really contains the event date. Likewise, a column containing a booking reference is not necessarily a subject; it may belong in the description so that the event title remains readable.

If the CSV includes fields such as categories, reminders, or all-day status, map them only when Outlook presents a matching destination field and the source values are compatible. A field may be ignored if the import wizard cannot interpret its values. After import, open one short event, one longer event, and one all-day event if present. Check the calendar view and the event’s details rather than assuming a successful wizard means every column was interpreted correctly.

Using new Outlook, Outlook on the web, or Outlook for Mac

New Outlook for Windows does not offer the same classic Import/Export wizard for CSV calendar files. A common route is to convert the CSV into an .ics calendar file, then use the calendar import option available in your Outlook version. In new Outlook and Outlook on the web, look for Add calendar and then Upload from file. Choose the .ics file and the calendar where its events should go. The exact labels can change as Microsoft updates the interface.

Outlook for Mac also does not use the classic Windows CSV import wizard. If you have a CSV, convert it to .ics using a trusted calendar application or the system that supplied the data. Then open or import the .ics file in Outlook for Mac; the available commands depend on the Outlook version. Check the destination calendar and the resulting events before relying on them.

An .ics file is designed to carry calendar events, so it can preserve details that a simple table may not express well, including recurring event information and timezone identifiers when provided by the source. Conversion quality still depends on the input. If the CSV does not contain a timezone or a recurrence pattern, converting it cannot recreate information that was never present.

Common import problems and how to fix them

Events are on the wrong day: Check whether the source uses month/day/year or day/month/year, and compare the file’s dates with Windows regional settings. Correct the source format and import a small test before repeating the full import.
Start or end times are missing: Reopen Map Custom Fields and confirm that the time columns are connected to Start Time and End Time, not to date fields or unrelated columns. Also check whether the source cells contain readable times.
All-day events appear as timed appointments: Confirm that the CSV has an all-day indicator and that it was mapped to a compatible Outlook field. If it does not, consider using an .ics export or correcting the events after import.
Descriptions or locations are blank: Check the mapping and inspect the CSV for empty source cells. A column heading alone does not guarantee that its contents were imported.
Some rows are missing: Look for blank start dates, malformed rows, or commas and line breaks that may have split a record. Open the CSV in a text editor if the spreadsheet view hides how the delimiters are arranged.
Events appear twice: The file may have been imported more than once. Remove the unwanted batch carefully, or use the wizard’s duplicate handling option on a future import. Outlook may not identify two events as duplicates if their details differ.

When correcting an import, avoid immediately importing the entire file again. First identify whether the original events landed in the intended calendar. If they did, remove or edit that batch before reimporting; if they landed in the wrong calendar, move or delete those items deliberately. This reduces the risk of leaving a mixture of old and corrected appointments.

Duplicates, recurring events, and later updates

The wizard’s duplicate choices matter most when importing a file that has already been used. Allow duplicates is useful only when repeated entries are intentional. Replacing duplicates can be convenient, but it should not be treated as a guaranteed update mechanism for every source: Outlook compares item details, and changes to a subject or date can make an existing event harder to match to the revised row. Do not assume that reimporting a changed CSV will neatly synchronize the calendar.

For recurring events, a CSV often contains either one row for the series or separate rows for each occurrence. A plain row does not necessarily define a recurrence pattern such as every second Tuesday. If the source offers an .ics export, use that for recurring appointments. If it only provides individual dates, those can be imported as separate events, but changing the pattern later may require editing each occurrence or rebuilding the series.

For a calendar that must stay current, use a subscription or synchronization method offered by the original service rather than repeatedly importing snapshots. A subscription typically displays a calendar supplied by another service and updates according to that service’s refresh schedule; it is different from copying editable events into your Outlook calendar. Confirm which behavior you need before choosing the method.

Alternatives when CSV is not the right format

Ask the provider for an .ics file first if the calendar contains recurring events, timezones, or event details that must be preserved. Use a published calendar link if you want ongoing updates and the source supports subscriptions. If neither is available, a calendar conversion tool can turn a well-structured CSV into .ics, but review its privacy terms before uploading data that includes personal appointments, customer details, or confidential locations.

For a small number of events, manually creating appointments may be safer than converting a poorly formatted file. For a large import, test a few representative rows in a temporary or otherwise suitable calendar before processing everything. Whichever route you choose, retain the original CSV and compare a sample of imported events against the source.

Frequently Asked Questions

Can I import a CSV calendar directly into new Outlook?
New Outlook does not provide the classic Windows CSV Import/Export wizard. Convert the CSV to an .ics file, then use Add calendar > Upload from file where available, or import it through a calendar application that supports the file.

Can I import a CSV calendar into Outlook on the web?
Outlook on the web generally imports calendar files in .ics format rather than using the classic CSV wizard. Convert the CSV to .ics first, then use Add calendar and Upload from file if that option appears in your account.

Will imported events update when the CSV changes?
No. A CSV import creates a one-time copy of the events. It does not keep Outlook linked to the file. Reimporting a revised file can create duplicates, so manage the old events or use a supported subscription if you need ongoing updates.

Can a CSV create recurring Outlook appointments?
Not reliably from a simple row of event details. A CSV may list each occurrence separately, but it may not describe a recurrence rule. Use an .ics export that includes the series information when recurring appointments need to remain recurring.

Why are my imported events showing at the wrong time?
Check whether the CSV contains separate, correctly mapped start and end times and whether its timezone matches the calendar. A CSV without timezone information can be interpreted according to local settings, so verify sample events and use an .ics file with timezone details when available.

Try it: the Date Difference Calculator: days, months, years and weekdays between two dates, with the DATEDIF formulas.

More in How-to basics

Sources: Function behaviour and menu paths: Microsoft Support documentation for Excel. Method & sources

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