Fines are heavy and and expect many boring situations if you do not exchange your driving license. To avoid a lot of troubles and save money, you have to apply for the exchange within two years, counting from the date of residence in Portugal to avoid taking your driving test again.
If you are from these groups of countries, please pay attention the following information:
Angola, Argentina, Brazil, France, India, Italy, Ireland, Macau, Morocco, Mozambique, Romania, Russia, São Tomé and Príncipe, Switzerland, Turkey, United Kingdom of Great Britain and Northern Ireland, United States of America, Venezuela.
Drivers from countries mentioned above, not resident in Portugal, are authorized to drive in Portugal for the first 185 days from their arrival. After that date they are in default, risking fines of up to € 500.