One thing is certain – being late is never a good idea, regardless of your reasons. If you are running late, you should at the very least call to give the person expecting you a heads up.
Many job seekers think, however, that the earlier you come for your interview the better. I disagree! While it is a great idea to be 5 to 10 minutes early, showing up half an hour in advance is not the best move. Sure, some interviewers have no problem making people wait (one of my former bosses even thought that she demonstrated authority by taking her time). Yet, most recruiters or hiring managers don’t enjoy carrying on with their tasks while someone is sitting at reception waiting for them. By coming very early, you are inevitably putting pressure on the person meeting you to hurry up and rush through their task at hand. Being ‘fashionably late’ is certainly unacceptable in the business world. Nonetheless, you do want to show that you too “have places to be and people to see”. So, circle the block a few times if you have to or go have a cup of tea before the appointment. When you walk in 5 or 10 minutes before your scheduled time, the interviewer is more likely to be ready for you and you are less likely to have made a negative first impression.