SINGAPORE - The taxman raked in record tax revenue in the last financial year as individuals and companies earned more and contributed to the Government's coffers.

Total tax collected for the 12 months to March 31 climbed to an all-time high of $43.4 billion, according to the Inland Revenue Authority of Singapore's (Iras) latest annual report out on Wednesday (Sept 23).

It was 4.4 per cent higher than the $41.6 billion collected in the previous financial year.

The number of millionaires increased by 326 - with 4,557 earning assessable income of over $1 million each, up from the 4,231 millionaires in the previous year.

Their combined income came to $8.63 billion and they paid about $1.60 billion in income tax.

In comparison, the previous year's millionaire batch had a total income of $8.04 billion and paid $1.48 billion in tax.

A further 14,757 people earned between $500,000 and $1 million each, up from 13,714 people in the previous year.

There continues to be a high level of voluntary compliance with on-time filing and on-time payment rates of 90 per cent on average, across all tax types, Iras said.

Tax arrears rose from 0.77 per cent of the total net tax assessed to 0.81 per cent.

Iras said it has tapped on business analytics to detect non-compliance more effectively.

"Our auditors and investigators are able to more accurately match and analyse data, and identify taxpayers with higher risk profiles," it said.

It investigated close to 13,000 tax evasion or fraud cases in the year, recovering about $450 million in taxes and penalties.

In a statement, Mr Tan Tee How, Commissioner of Inland Revenue, thanked taxpayers and stakeholders for the "trust and confidence in our tax system."

"Taxpayers and supporting nation-building by filing and paying on time. We will continue to simplify the tax rules and filing and payment processes, thereby enhancing voluntary compliance."