Factsheet
15/03/2026
2026-03-15
1:29 am
15/03/2026
2026-03-15
1:29 am
american english - Date format in UK vs US - English Language & Usage Stack Exchange
Change date format from US MM/DD/YYYY to UK DD/MM/YYYY
UK Date Format options
How can I change the Date format from US to UK in OneDrive Online
How this standard meets user needs
Users of this standard include:
- publishers of government data
- archivists
- data scientists
- data analysts
- developers
Using the ISO 8601 standard means you’ll have:
- more consistency in how your systems format data
- the flexibility to choose how precise you make the date and time
- an easier way to sort documents by date and filename
- improved ability to exchange data internationally, without issues with time zones and date formats
The ISO standard documentation and its BSI equivalent are not free of charge. There are other profiles available for this standard which are free of charge including:
- the IETF RFC 3339
- the W3C date and time format note
- other independent published guidance that summarises the standard
How to use the standard
Use the ISO 8601 format to the level of accuracy you need when you’re recording or exchanging a date, or date and time, in a system. The minimum level of accuracy for this standard is four digits representing a year.
List date and time elements in descending order of size (years, months, days, hours, minutes, seconds, milliseconds and microseconds). If you’re using ‘time’, separate it from the ‘date’ with ‘T’, use the 24-hour format and a colon to separate hours and minutes. You can also separate each value with hyphens to increase readability. For example, YYYY-MM-DD-THH:MM-SS. You can refer to midnight as either 00:00 or 24:00 so your documentation should be clear whether you’re referring to the start or end of the day.
This profile assumes that you’re using local time. You can add a Coordinated Universal Time (UTC) offset. For example, 2017-05-16T10:30:56+01:00 is 16 May 2017 10:30 and 56 seconds with an offset showing British summer time (BST), one hour ahead of UTC.
ISO 8601 is also compatible with other date standards such as:
- RFC 3339, which simplifies ISO 8601 for use in internet protocols by leaving out infrequently used levels of accuracy
- W3C date and time format, which is an ISO 8601 profile written to simplify its use in WWW standards
ISO 8601 is also used in the following open standards for government:
- Exchange of calendar events - iCAL
- Exchange of contact information - vCard
- Sharing or collaborating with government documents - ODF 1.2
- Open contracting data - OCDS
- Publishing international development data - IATI
- Publishing job vacancies - JobPosting
- Share information between emergency services with MAIT
- Publishing government documents HTML5
Summary of the standard’s use for government
Use the ISO 8601 standard for machine-readable dates and times in:
- APIs
- data for transferring between systems
- date sorting, for example at the start of filenames
This standard does not apply when human readability is the main concern. For example, dates and times added within the text of a document. The GOV.UK Design System has guidance on using dates in digital services.
This profile uses the 2004 version of the standard as it still meets the government’s needs.
The government chooses standards using the open standards approval process and the Open Standards Board has final approval. Read more about the approval process for selecting ISO 8601.
Videos
Hello to those from the UK,
I'm seeking some clarification regarding the correct or most common format for writing the month and year in the UK, specifically in numerical form.
I’ve encountered both “YYYY-MM” (eg 2013-06) and “MM/YYYY” (eg 06-2013) and am perplexed about which format is widely accepted or preferred within the UK.
Does one format tend to be favoured over the other in certain contexts? Are there official guidelines that recommend one format for specific use-cases, such as professional correspondence, academia, or governmental use?
Thank you so much for any insights you can provide!
Although there are people who will sometimes say:
- Today is Thursday, the 24th of May, 2012.
There are also others who instead say the same thing this way:
- Today is Thursday, May 24th, 2012.
Certainly in the United States, the second way of mentioning a date is more common than the first. The long form sounds more formal to us, as in “on the Fourth of July” being more formal and long-winded than simply saying “on July 4th”.
It was pronouncing the month before the day out loud that gave to retaining that same original order when converted to digits: merely convert the month name to a natural number, and there you have your answer. What’s today’s date? It’s May 24th. Instead of writing May-24, we simply change the “May” to “5” and write 5-24 or ⁵⁄₂₄.
That way it follows the natural language order and so requires no mental gymnastics to switch things around when speaking the date aloud. Similarly “September 11th” gets written ⁹⁄₁₁, etc.
The full spoken form with the year, “May 24th, 2012”, then becomes the written shorthand “5/24/2012”, or often just “5/24/12”. “Christmas of 2001” can be, and somewhat annoying often is, written “12/25/1”, while “January 25th, 2012” becomes “1/25/12”.
This isn’t usually any sort of problem because of universal consensus on how to interpret such things in the United States. If you write day/month/year in America, you will not be understood. Although I myself prefer the ISO notation, normal people do not use it in their daily affairs.
It's very possible that the US inherited this from an outdated English format - much like the length unit, after Henry III's foot and which the English have left behind in favour of the more logical metric system.
One argument I've heard in favour of the American system of dating is that the numbers of months in a year is smaller than the number of days in a month which itself is smaller than the number of possible years. So you would have 12/31/2013, in ascending order. I don't really buy this argument, but OP might be interested in it anyway so here it is.
Meanwhile, in Northern Europe they've moved on to an opposite, descending date standard: year/month/day.
Hi thanks for your message. I have tried what you suggested but to no avail. When I first login you'll see from the screenshot that it says English (United States) but when I click on English (United States) it says English (United Kingdom) Your Display Language.....
Hello Petesmit66! I'm Gunasekar and I'd be happy to help you with your question.
I understand that you would like to change the date format to DD/MM/YYYY in your OneDrive account online. To change the format,
a. Go to https://onedrive.live.com/ b. Sign in with your Microsoft account. c. Click the Gear icon and select the language (see image 1)
d. Once you changed the display language to united kingdom, Sign out from your account on OneDrive and Sign in again.
If the issue persists, try changing the regional settings (language and date format) and sign in with your account again.
Give back to the Community. Help the next person who has this issue by indicating if this reply solved your problem. Click Yes or No below.
I hope this information helps. If you have any questions, please let me know and I will be happy to help you further.
Best regards,
Gunasekar N
Here is a solution without using a formula:
- Select the relevant columns
- Choose Data → Text to Columns…
- Select “Delimited” and click Next
- Untick all delimiters and click Next
- Select data column format “Date: MDY” and click Finish
The dates should now be converted to UK dates.
The problem is that a US date can parsed by Excel as a UK date when the day is less than 13. When this happens Excel converts it to the localized UK serial (date) number.
So 03/19/2014 is obviously a US date of the 19th of March. However 05/03/2014 is ambiguous so Excel parses it the local date format as the 5th of March, rather than the US 3rd of May. Any formula has to check if Excel has stored the US Date as a UK date. A UK date will be stored in Excel as a number.
=IF(ISNUMBER(A2),DATE(TEXT(A2,"yyyy"),TEXT(A2,"dd"),TEXT(A2,"mm")),DATE(RIGHT(A2,4),LEFT(A2,FIND("/",A2)-1),MID(A2,FIND("/",A2)+1,2)))
(For a US date in cell A2 and PC date is dd/mm/yy).
If ISNUMBER is true, the US date looks like a UK date and Excel has serialized it as a number. So can format the date as text and back to a date again. Note day is passed to the month parameter of the first DATE function to perform the conversion.
If ISNUMBER is false, its stored as a string as Excel doesn't convert a date string with >12 months. So use string functions to split it up for the DATE function.