Currency
Belgium is in the Euro zone, sharing a common currency with Austria, Cyprus, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Malta, Slovenia, Spain, Portugal and The Netherlands.

Of the older EU countries, Sweden, Denmark and the UK remain the outsiders. Most of the newer EU countries plan to adopt the Euro when they are ready to do so, but each has its own timetable for convergence with Slovakia aiming to be the next member from January 2009. Euros from any of the 12 countries may be used anywhere in the EU.

Coins:  1 cent, 2 cents, 5 cents, 10 cents, 20 cents, 50 cents, 1 EUR, 2 EUR
Notes:  5 EUR, 10 EUR, 20 EUR, 50 EUR, 100 EUR, 200 EUR, 500 EUR

On one side of the coins is a European Union emblem showing a map of the Euro zone surrounded by the 12 stars of the Union.  On the other side is a design specific to the country where it was minted. There is talk of abolishing the one and two cent coins to improve the trouser line. All Euro notes are the same, regardless of which country they come from, and feature symbols representing co-operation, openness, dynamism and harmony.  

Paying for Goods and Services

Cash
Cash dispensers are usually found wherever there is a bank, and they all take the Bancontact/Mister Cash cards issued by local banks as well as credit cards. Dispenser lobbies within banks are open after hours and are usually only for customers of that specific bank and most don’t issue cash on credit cards. You'll need to swipe your bank card to get in. There is an irritating lack of machines in central Brussels which means queues at peak times. Machines can often be drained dry on a Saturday night, thereby frustrating Sunday morning customers.

Debit and Credit Cards
The most common card in Belgium is the Bancontact/Mister Cash card.  It is linked to your current account, and is accepted in department stores, supermarkets, gas stations, and high street shops.  It’s a good idea to have one of these, as there are still many places in Belgium that don’t accept alternatives.  A Bancontact/Mister Cash card with a PIN number will be issued when you open a Belgian bank account.  

Most types of credit card are widely accepted. If you get a Visa or MasterCard from a local bank, the standard option in Belgium is for this to operate like a debit card, with the full balance taken from your account each month. Some of the major banks do offer credit cards (Visa Pinto for example, from KBC bank) but these can be expensive. Diner's, American Express and other major international credit cards can also be obtained and used in Belgium.

Proton
Belgium is a pioneer of the cashless society. The Proton card is actually a chip integrated into your Bancontact/Mister Cash card and is like a rechargeable electronic purse. It is designed to pay for everyday items such as newspapers and sandwiches, as well as paying the butcher and the baker. 

This is how it works: Using your usual four-digit PIN code, you load the card at a cash dispenser, and then go shopping.  The shopkeeper enters the amount to be paid into the Proton terminal, and you put your Proton card into the terminal.  When the amount to be paid appears on the screen, you simply press the OK button, and the payment is made. A word of caution: a lost card is like lost cash so don’t overload the card.

(Expatica 2008)