Re: Create Item for SharePoint Event Calendar - All Day Event
Hi @Anonymous ,
You could add a Compose to save the date firstly, and then you could format the date time as my screenshot below:

Expression for the start time as below:
formatDateTime(outputs('Compose'),'yyyy-MM-ddT00:00:00Z')
Expression for the end time as below:
formatDateTime(outputs('Compose_2'),'yyyy-MM-ddT23:59:00Z')
Best regards,
Alice
Community Support Team _ Alice Zhang
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