You can use your MasterCard when paying in car parks. The vast majority of car parks support MasterCard, especially the large car parks such as lnterparking and Qpark.
When parking in the street, you may not be able to pay with your MasterCard or cash. In these situations, you can usually pay by text message or useful parking apps.
In Belgium you can use services such as 4411 (www.4411.be) and parkmobile (parkmobile.be). These services are billed monthly through your mobile phone bill or by direct debit.
In the Netherlands you can use Yellowbrick (www.yellowbrick.nl) or Park-line (park-line.nl). These services are billed monthly either through your MasterCard or other methods. 15 Belgian municipalities also already support Park-line.