The following is a list of many bugs caught on or near leap day, February 29th, 2020.  Each link below references the issue with supporting details where available.  This list does not include bugs that were already caught and repaired before they could have impact on leap day.

Last updated 2020-05-25 11:32 PM PDT

Verified / Unresolved

Items in this section have been verified, and have not yet been resolved.

Verified / Fix Pending

Items in this section have been verified, and have a fix ready - pending release.

Verified / Resolved

Items in this section had an impact on or near February 29th, were verified as actual bugs, and are now reported as resolved.

Verified / Deferred

Items in this section had an impact on February 29th, but were either resolved through manual workarounds, or resolved themselves on March 1st without any specific fix or resolution reported.  One assumes that the responsible party will take appropriate action before the next leap day in 2024, or has already taken such action, but to the best of my knowledge no confirmation of that has yet been provided.

Verified / Uncertain Cause

Items in this section have been verified to have occurred near the leap day, but may or may not have been caused by a leap year bug.

Verified / Not a Leap Year Bug

Items in this section have been verified to have occurred near the leap day, but were confirmed to not have been caused by a leap year bug.

  • The stock trading platform Robinhood experienced multiple system-wide outages on March 2nd and March 3rd, that many people attributed to the leap year. Robinhood disagreed, stating:

    The outage was not caused by a failure to code for the leap year. We had instability in a part of our infrastructure that allows our systems to communicate with each other.

    Reportings: 1, 2, 3, 4, 5 (and many others)

    A Robinhood engineer also later confirmed that it was not leap year related.

  • The certificate authority Let's Encrypt had an issue related to CAA Rechecking on Feb 29th. The bug was not related to leap year.


These items surfaced during my search or were brought to my attention by others, however I have not been able to confirm their validity.  They may possibly not have happened at all.

  • Several people reported that surgical air suction pumps in operating rooms at various hospitals, and other unspecified hospital software, went offline on Feb 29th.
  • Some reported the date on their wristwatch skipped over the leap day, including a Timex Expedition watch, and a Casio watch.  Another person gave a photo of various Casio watches including several that were working correctly, and an F91W-1 which was not (though that is by design since that model does not keep track of the year, per its documentation.).
  • A user of the app for a Brazilian supermarket, Pão de Açúcar, highlighted a possible error with the app on Feb 29th.
  • A person reported a possible bug with Patreon
  • Some people reported probable leap year bugs with their Amazon purchase experiences.  Reports: 1, 2, 3
  • Several users of Google Maps have seen wildly incorrect routes for transit navigation on in King County, Washington, USA on Feb 29th.  It's unclear if the issue is with Google Maps, or with the underlying data source.  Reports: 1, 2
  • A person reported that all of the Yealink T56 business desk phones displayed February calendar events for the wrong day.
  • One person reported that LinkedIn listed the time they had been with their current employer incorrectly.
  • A firearms dealer reported that the E4473 software released by the US Bureau of Alcohol, Tobacco, Firearms and Explosives is having trouble operating correctly today.  This software is used by gun dealers to electronically complete Form 4473, registering firearms purchases.
  • One person contacted me directly to share a screenshot of the Todoist mobile app, showing "Tomorrow Sat Feb 29", even though it was already Feb 29.
    Another person shared a problem with Todoist losing streak data on Feb 29th.
  • A person contacted me directly and shared that the French post office system had a nation-wide bug on the 29th that prevented anybody from sending parcels.  (Here is a tweet showing long lines at the post office.)
  • A user of ElasticSearch's legacy client library for JavaScript opened an GitHub issue claiming problems querying data for Feb 29th.
  • One person reported on March 1st that their Apple Watch was giving incorrect exercise data for February.
  • A user of a Tandem Diabetes insulin pump with Control IQ software shows us a video, and reports incorrect IOB data during the transition between Feb 29th and March 1st.
  • A person reported a problem with their Sensi smart thermostat not showing data for Feb 29th.
  • A person shows us that their experience with the Chuck E. Cheese Sketch Book (photo booth) printed a date of March 1st when it was actually Feb 29th.
  • A person reported a problem with the Turkish government's tax filing system, Defter-Beyan, which allegedly didn't allow February 29th as a valid date.  It gave an error message that the declaration period has passed although it hadn't.
  • A person reported that the date could not be set to Feb 29th 2020 on a Medisana BU 510 blood pressure monitor.
  • A person reported that his transaction dates on PiggyVest, a Nigerian online savings and investing platform, were all displaying Mon Jan 19, 1970 when it was March 1st, 2020.  Earlier, on Feb 28th, PiggyVest themselves quipped "February 80th 😫", but it is not clear if they were referring to their platform or not.
  • One person reported that cash registers and rewards systems at Qdoba were down on Feb 29th.  It's unclear if this was a just single location or if it is related to a leap year bug or just coincidentally timed.
  • A person reported that the alarms on his Sonos smart speaker went off on Sunday March 1st, though they were only scheduled for Monday through Friday.  It's unclear if this was related to a leap year bug or just coincidentally timed.
  • A person reported that his Chase online banking app showed the same credit card payment twice - first on Feb 29th, then duplicated on March 1st.

Honorary Mention


You might also be interested in these other articles I've authored on the subject of leap year bugs:

Please let me know (in comments below, or send me a DM on Twitter) if you have any corrections or additions.  Thanks.