IT'S official. From June 13, Singapore's 5.8 million mobile subscribers will be able to to switch operators without giving up their existing numbers.

The eagerly-awaited announcement by the Infocomm Development Authority of Singapore (IDA) on Wednesday will give mobile phone users greater flexibility and choice of subscription plans, and boost competition among the telcos, which will have to offer better deals in future.

The Full Mobile Number Portability will replace the current solution where a mobile subscriber needs two numbers, so that calls to his old number are forwarded to a new one.

IDA said from June 13, anyone who wishes to keep their current number when they switch mobile operator, can do so by the next working day.

This spares them the hassle of updating their family, friends, and business contacts about a new number.

The new scheme allows a mobile subscriber who has switched operator to:

-- Retain full use of his mobile number, which will continue to appear on his contact's Caller-ID when he makes a call or uses the Short Message Service (SMS) or Multi-Media Message Service (MMS).

-- Continue receiving MMSes on his number from his previous mobile operator.

Pre-paid mobile subscribers can also enjoy the same benefits of retaining their numbers when they switch mobile operator.

IDA Deputy Chief Executive and Director-General (Telecoms) Leong Keng Thai said on Wednesday: 'Full Mobile Number Portability is expected to bring about a sea-change in Singapore's mobile market.

'Consumers will be empowered with greater flexibility to choose from the offerings from mobile operators. This in turn intensifies competition and pushes the operators to work harder to attract and retain their customers.

'As we can expect to see more competitive pricing or better value-for-money mobile service deals, even those who choose to remain with their current mobile operator should benefit.'

The move is also expected to open the doors to new business opportunities for non-traditional telecommunication service providers like wireless broadband providers and Voice-Over-Internet Protocol (VoIP) providers.

IDA said there are about 130,000 mobile subscribers who have ported their numbers under the current Call-Forwarding solution. This group of subscribers will migrated in an exercise from April 22.

As part of the migration exercise, these subscribers will be contacted by their current mobile operators, who will advise them on the migration procedures.

These subscribers will need to:

-- Decide by May 14 which number to keep - either the old number from the previous mobile operator or the new number issued by the current mobile operator, otherwise the new number will be assigned to them by default.

-- Consider informing their contacts about their choice of number ahead of June 13, which is the deadline for migrating mobile subscribers on the current scheme to the new solution.

Consumers can also refer to the Frequently-Asked-Questions on Full Mobile Number Portability on IDA and the respective operators' websites, to find out more about this new solution and its benefits.