Actually you do need to check for <= instead of just < beacause if one of the
periods ends at the same date as the start of the other the < check would be
false .

"Harlan Grove" wrote:

"KL" wrote...
Your formula can be further reduced to:

=AND(Start2<=End1,Start1<=End2)
....

Technically this wouldn't be overlap is either but not both conditions were
TRUE due to exact equality. Drop the equal signs