Cleaners' basic pay will go up by $200 in the next three years, starting from next July. It will then rise yearly by 3 per cent for three years.

Those employed by the same business for at least 12 months will get a yearly bonus, starting from 2020, of two weeks of basic monthly pay.

The recommendations, unveiled by the Tripartite Cluster for Cleaners (TCC) yesterday, further boost the wages of some of Singapore's lowest-paid workers.

Said National Trades Union Congress assistant secretary-general Zainal Sapari, who chairs TCC: "The (change) may be seen as a half-step, but (it) is a big half-step. This is the first time we are forcing an industry's annual increments, as well as some form of bonus."

The Government has accepted the recommendations, which will benefit about 40,000 Singaporeans and permanent residents employed by more than 1,200 cleaning firms.

Companies with service contracts that start before next Julyhave until July 1, 2018 to comply with the recommended wages.

The TCC suggestions follow its review of the progressive wage model in the cleaning industry. The modelaims to raise the pay of low-wage workers through skills upgrading and improvements in productivity.

It applies to the cleaning, security and landscape sectors, and became compulsory for the cleaning industry in September last year.

The model specifies a starting pay of at least $1,000 a month for cleaners, with wages rising to $1,400 and more for higher-skilled cleaners, and from $1,600 for supervisors.

The median basic wage of full-time cleaners grew by 9 per cent per annum from 2012 to last year. It was $1,100 in June last year.

Said Mr Zainal: "We need to make employment terms and conditions better. Otherwise, the type of workers attracted to the cleaning industry will be the vulnerable ones."

Correction note: The story has been edited to clarify that the median basic wage of full-time cleaners grew by 9 per cent per annum from 2012 to last year.