Singapore companies classified incorrectly an average of 100 workers annually in the last three years, Minister of State for Manpower and National Development Zaqy Mohamad said yesterday in Parliament.

In total, 308 such alleged cases were received by the Ministry of Manpower (MOM) and Central Provident Fund (CPF) Board during this period, with 160 cases involving workers being misclassified as self-employed.

Self-employed people do not receive benefits that employers are legally obliged to provide for their workers, like CPF contributions.

He gave the figures in his reply to labour MP Patrick Tay (West Coast GRC), who asked if more can be done to punish errant employers who misclassify their workers, and educate casual workers who have no fixed working days or hours.

Mr Zaqy said errant companies have been punished with, among other things, warnings and late payment fees.

He also said that in all but two cases, the misclassified workers were paid what was due to them, including overtime pay and CPF contributions. The two were prosecuted, with one of them settling the case out of court while the other is appealing against the conviction.

He said: "Rest assured that MOM and CPF will investigate the cases... to ensure that employers make good their obligations and to pay affected employees what are due to them."

Nominated MP Anthea Ong asked if MOM could do an in-depth study on legal protection for casual workers in other countries in order to develop a framework on the rights and benefits of casual workers in Singapore.

Casual work employees comprised 3.4 per cent of resident employees last year, down from 5.1 per cent in 2009.

Mr Zaqy noted that casual workers are covered by various laws, including the Employment Act and CPF Act.

They are entitled to timely payment of salary, CPF and protection against wrongful dismissal, he said, adding that workers who are employed for at least three months are also entitled to paid annual and sick leave.

According to the MOM website, a self-employed person operates his or her own trade or business. Such a person may work in diverse occupations, including real estate agents, private tutors and private-hire car drivers, says the website.

Mr Zaqy noted that other jurisdictions may have seen a rise in the number of self-employed people engaging in casual work.

But in Singapore, "we cannot equate self-employed persons with casual workers", he said. For example, taxi drivers are self-employed but work regular shifts, he added.

He also said the proportion of self-employed people, whose main job is operating their own trade or business, has remained at between 8 per cent and 10 per cent of the resident workforce in the past 10 years.

Surveys show that the self-employed want greater flexibility and autonomy.

Mr Zaqy said: "In fact, there was a drop in the number of self-employed persons last year, due in part to the tighter job market."