* Goes to bed at 12:30 a.m. or later
* Prefers to get up in the morning at 10:00 a.m. or later
* Takes a long time getting out of bed – wakes very slowly – is grouchy when required to get out of bed earlier than preferred
* Isn’t alert for some time after getting out of bed in the morning
* Needs an alarm clock to wake
* Prefers to finish things or work on something later in the evening or through the night if necessary
* Participates in physical activity later in the afternoon or evening
* (If so inclined) naps around 7:00 o’clock in the evening
* Prefers to have lunch around 2:00 o’clock in the afternoon
* (If forced to get up early for work) will revert to night owl schedule on the weekend or on days off
* Will compensate for lost sleep by sleeping later in the morning
* Prefers to work or do things later in the morning or later in the afternoon
* Is usually awake and alert for late night social activities
* Has an energy spurt after 9:30 p.m.
* Finds travel east or change to earlier morning schedule a difficult adjustment
* Finds travel west or change to later evening schedule an easier adjustment
* May be chronically tired if forced to rise early over a long period of time