Yes, there are a few disadvantages of taking an add-on credit card for a primary card holder. The disadvantages are:

- You can ruin your credit history:When you take an add-on card, you are giving someone else the ability to make or mar your credit history. This is because the secondary card holder’s part repayments, or repaying only Minimum Due Amount is linked to the primary card holder and any late payment or default can ruin the primary holder’s credit history that he/she may have spent years creating

- You’ll have to shell out more for an add-on card:Very few banks offer add-on cards free of charge. Even if the bank doesn’t charge you any annual fee, it is more likely to charge you a one-time payment for availing the service of an add-on card.