Need a "Completed date" column: is there a "last updated" or similar formula?

[Phil_Sheard]

We’re using AirTable to track actions and filtering the todo list using a checkbox field titled “Completed”.

I’d like to setup a new view that sorts the tasks with most recently completed at the top.

Manually adding the “Completed date” isn’t an option as people will naturally forget to fill it in.

I’ve looked down the list of available formulas but nothing jumps out as being suitable.

Thanks in advance for any help.

[Dakota_Bushnell]

Recently I discovered that the “Last modified time” field was rolled out.

I used this to my advantage by creating a “Completed” checkbox, and then using a formula to link to when that checkbox was checked.

The formula for my “Completed Date/Time” column is as follows:

IF({Complete Checkbox} = 1, LAST_MODIFIED_TIME({Complete Checkbox}))

I also made sure to turn off the “Use the same time zone (GMT) for all collaborators” feature so that the time reflected correctly for us, as shown below:

I hope this helps!

[Chad_Taylor]

Thank you so much, this is exactly what I was looking for! Simple and 100% inside Airtable.
Thank again.

[Sean_O_Shaughne]

To build on this a bit as I think new functionality makes this really easy now. Create a new field using Last Modified Time. You can have that field only look at when one field was updated (in my case Done for my Task List). Now, whenever you update the record by changing the status of Done, you have the Date / Time stamp.