When is the next leap year on a Saturday?

"Leap Year" is an entire calendar year with 366 days. An entire year cannot be
compressed into a single day.

Perhaps you're asking for the next leap year in which the added day ... February 29 ...
will fall on Saturday. That will be the year 2020 .
"Leap Year" is an entire calendar year with 366 days. An entire year cannot be
compressed into a single day.

Perhaps you're asking for the next leap year in which the added day ... February 29 ...
will fall on Saturday. That will be the year 2020 .