Holiday calendar import checklist: inspect, import and update safely

Choose a holiday file, check all-day dates, avoid duplicate imports and maintain an updated calendar.

Updated September 19, 2026 · HolidayDates.net

Choose the file that matches your purpose

HolidayDates provides CSV files for inspecting and organizing rows and ICS files for calendar events. Start with one country and one year when that is all you need. A combined file is convenient for a regional team, but it also adds events for places that may not affect your work. Read the country name and year before downloading. The files are public date references; they do not include your employer’s confirmed closure schedule, personal leave or private appointments.

Use CSV when you want to sort, compare or annotate the data in a spreadsheet. Use ICS when you want all-day entries alongside an existing calendar. Do not treat the CSV as a universal calendar-app import template: calendar applications can require their own column names and fields. The download page lists the fields supplied here so you can see what information is present before deciding how to use it.

Inspect the source and coverage first

Open a few rows in the CSV and compare the dates and names with the corresponding country page. Review the type, note and source fields, especially when an entry has a limited sector scope or is marked as a reference date. An official source URL is a way to check the information; its presence alone does not prove that a particular file contains every date from the latest announcement. Read the page’s coverage notice before using the file for a critical decision.

Check the selected year rather than assuming the file changes automatically as time passes. Future-year arrangements can be incomplete or require later reconciliation. Make a note of when you downloaded the file and which version you used for a customer promise or travel plan. If you find a discrepancy, keep the exact row and source page so that the issue can be investigated without relying on an approximate recollection of the date.

Create a separate destination calendar

Import public holidays into a dedicated calendar rather than mixing them permanently with personal meetings. Give it a clear name such as the country and year, and review its sharing settings before adding private notes. The imported events already contain public holiday information; your customer names, order details and contact information belong in your own planning system. Keeping those separate makes it easier to replace public dates without exposing or losing private work.

In your calendar application, use its documented import function and select the intended destination. Menu names and supported import behavior vary by application and version, so follow the application’s own help if the controls differ. This guide does not claim that every calendar product has been tested. Start with a small country-year file and inspect the result before importing the combined regional calendar.

Check all-day dates after import

The ICS files represent public dates as all-day events. An event for one date has an exclusive end date on the following day in the iCalendar format; that does not mean the holiday lasts for two days. After importing, open several entries and confirm that the calendar displays the intended date and country. Include an observed holiday, if the file contains one, so you can see whether its label remains understandable.

Keep timed meetings distinct from these all-day references. A meeting needs an agreed time zone and clock time, while a public holiday is tied to the local calendar date. If your application displays an unexpected date, inspect the event and import settings before changing the underlying holiday record. Do not repair a display problem by moving an official date without checking the country page and the original source.

Understand availability and working-day limits

Public holiday entries in these files are informational and marked transparent in the calendar format. They are not intended to reserve meeting time or declare that every colleague is unavailable. Your application may also have its own availability behavior, so inspect an imported entry rather than assuming it blocks appointments. Ask the relevant people to record their actual absences separately, especially when their working pattern differs from a standard weekday schedule.

A holiday file is also not a complete business-day calculator. It does not supply every normal weekend, company shutdown, school vacation or make-up working day. Where a country page includes adjusted workdays in its schedule, check those separately before calculating a production deadline. A project tool that automatically excludes all Saturdays can still give the wrong result even after you import every holiday event correctly.

Avoid duplicate imports and false update expectations

Downloading and importing an ICS file is different from subscribing to a maintained calendar feed. Treat these files as snapshots. A later website update will not necessarily change the events you already imported. Before importing a replacement file, check how your application handles an existing event identifier and whether it creates duplicates. Do not assume that all calendar products update events in the same way simply because the file uses stable identifiers.

A separate destination calendar makes the replacement process easier to control. Review any private changes you added before removing or replacing old events, and use the application’s normal backup or export option if needed. Import into a temporary test calendar first when the update behavior is uncertain. Compare a few changed and unchanged dates before deciding which copy the team will use for future planning.

Finish with a practical verification pass

Check that the country, year, event count and a sample of dates match the downloaded file. Confirm that names and notes remain readable and that the public calendar has not unexpectedly become visible to a wider audience. Then compare the dates that matter to your actual trip or order with the authority and service provider involved. A correctly imported file can still be insufficient for a delivery promise if a receiving warehouse follows a different operating schedule.

If something looks wrong, record the filename, calendar application, affected date and what you expected to see. Remove private information before sharing a screenshot or sending a correction request. Keep the original file so you can distinguish a source-data issue from an import problem. Use the download page to obtain a fresh copy when appropriate, and retain the public-source check as part of your normal planning process rather than treating import success as the final verification of every date.