SINGAPORE - A renovation contractor who failed to register for goods and services tax (GST) has to pay a total of $504,501 in back-dated taxes and penalty.

Chong Wee Keng, who owned D'Esprit Design and Renovations at Tradehub in Boon Lay Way, was also fined $4,500 on Friday after pleading guilty to the offence.

This is the third case to be dealt with this year, the previous two involving companies.

Registration is compulsory for any firm with a turnover of more than $1 million.

Investigations by the Inland Revenue Authority of Singapore (Iras) showed that the 53-year-old was liable to notify the Comptroller of GST of his liability to register for GST by Oct 30, 2006. But he failed to do so.

Chong must now pay $458,637 of GST that he did not account for between December 2006 and December 2010.

On top of this sum, he has to pay a penalty of 10 per cent of the tax due - $45,864.

A statement from Iras said businesses should regularly assess if they need to register for GST. If the turnover for the past four quarters or expected turnover for the next 12 months exceeds $1 million, businesses must notify the Comptroller of GST of its liability to be registered for GST within 30 days of the end of the fourth quarter.

Businesses that fail to register for GST can be fined up to $10,000 and face a penalty equal to 10 per cent of the tax due from the date on which the business is required to register for GST.

The effective date of GST registration for a business will be back-dated to the day that its liability to register arose.

Businesses will have to pay the outstanding GST on all its past transactions since the effective date of registration, even if this amount was not collected from its customers.