Is coughing for a week normal? Do I need to go to a doctor if I have been coughing for last five days? How long does a cough last usually? These are some of the things most people worry about when they cough as it usually doesn t subside easily. However if you thought a cough could last around a week or 10 days then you are wrong. Because according to a 2013 study published in the Journal Annals of family medicine  it is proved that a cough can last for around 18 days which is roughly three weeks.