The payment performance of Singapore firms took a turn for the worse after three quarters of improvement, with partial payments hitting a near four-year high in the first quarter of 2016.

Prompt payments in the year's first quarter accounted for less than half of all payment transactions while slow payments made up more than two-fifths of payment transactions for the first time since the third quarter of 2015, according to the Singapore Commercial Credit Bureau's latest payment statistics released yesterday.

Overall, prompt payments fell to 41.11 per cent in the first quarter - its second lowest reading in a year. However, it was a slight improvement on a year-on-year basis, inching upwards by 2.07 percentage points from 39.04 per cent in the first quarter last year.

Prompt payment refers to when at least 90 per cent of total bills are paid within the agreed payment terms, while slow payment is classified as when more than 50 per cent of total bills are paid later than in the agreed credit terms.

Slow payments have similarly deteriorated to its second highest reading in a year.

On a quarter-on-quarter basis, slow payments jumped by 11.15 percentage points from 35.43 per cent in the fourth quarter of 2015 to 46.58 per cent in the first quarter of this year.

Meanwhile, partial payments rose to its second highest peak in four years, climbing by 0.84 percentage points quarter on quarter for the fourth consecutive quarter, from 11.47 per cent in the fourth quarter of last year to 12.31 per cent in the first quarter of 2016.

On a quarter-on-quarter basis, slow payments deteriorated across all five industries. This stands in contrast to the fourth quarter of last year, when only one of five industries experienced an increase in slow payments.

Correction note: An earlier version of this story stated that slow payments in this year's first quarter made up two-thirds of all payment transaction. This figure we were supplied with is wrong and the number should be two-fifths instead.