An Overdue Fine is an automatic fine charged upon checkin or renewal when all following conditions are met:

• item is overdue
• fine accrual is defined in Overdue Fine Policy (Settings → Circulation → Overdue Fine Policy)
• fee/fine owner is defined for the service point of checkin/renewal (Settings → Users → Owners)

Amount calculation logic

Assume following scenario:

• item is overdue by 2 days and 5 hours
• item is being checked in
• applicable Overdue Fine Policy is configured to charge $5 per day:

1) Calculate overdue time in minutes:

(2 days * 24 hours per day + 5 hours) * 60 minutes per hour = 3180 minutes

If option "Count closed days/hours/minutes" is set to "No", the resulting number will be reduced by the number of minutes the library was closed

Only whole minutes are taken into account, seconds are discarded

2) Calculate number of minutes per interval defined in policy:

1 day * 24 hours per day * 60 minutes per hour = 1140 minutes

3) Calculate the number of whole overdue intervals:

3180 minutes / 1440 minutes = 2.2 intervals

Fractional result is rounded UP: 2.2 → 3 intervals

4) Calculate fine amount:

3 intervals * $5 = $15