"The day of action is a success," the Christian union federation (CSC) said in a statement.
In the midst of the financial crisis sweeping through Europe, Eurostar trains to London and Paris as well as high-speed Thalys services to France, Germany and the Netherlands were suspended.
Rail services were also stopped in the southern region of Wallonia and were infrequent in Flanders to the north.
Road traffic in the capital was also lighter than normal, with many non-strikers opting to take the day off.
In Belgium's second city of Antwerp, creches, museums and libraries were closed while in Bruges all public offices remained shut.
Charleroi and Liege in the southern region of Wallonia were also affected.
The strike action took place the day after French bank BNP Paribas took a controlling interest in Belgium's largest banking group Fortis, which has been subject to three different bailout packages in a week.
Members of the liberal CGSLB union took to the streets outside the Brussels stock exchange distributing leaflets saying "purchasing power, what's left? Peanuts".
"The message is clear," said Philippe Vandenabeele, the union's secretary general.
"We are calling for better purchasing power for workers. There aren't the reserves left and it's time to think now of Mrs Everywoman rather than thinking of the banks."
Thierry Bodson, the general secretary of the Wallonia wing of the FGTB, one of the country's biggest trade unions, told local radio that one of the strikers' key demands was a reduction in energy costs via lower consumption tax on oil, gas and heating fuel.
While the level of protest differed from region to region, meaning the action fell short of a general strike, Bodson recalled that in June about 100,000 people had taken to the streets to protest against the steep rise in living costs.
In September, consumer price inflation in Belgium hit 5.46 per cent.