AT has added 6500 extra spaces to buses and trains to deal with the madness, but passengers have been warned they may be forced to wait for transport due to full services.
AT metro operations' manager Brendon Main also recommended commuters travel outside peak times where possible.
"We just ask people to show a little more patience as we move through March. It's the busiest month of the year," he said.
"Those that can travel outside the peak times - that could be a good idea."
Main said the boost in public transport capacity and services would "go a long way" towards meeting demand.
"We want to ensure that wait times are acceptable and, on some routes, better than last year."
Traffic congestion usually eases in April as students timetables settle and workers take breaks during the Easter holidays.
In March last year 1157 complaints were made about buses being late, full, overcrowded or not showing up.