The existing 1 million mobile phone users on the 900-megahertz band can continue using the service until the 900MHz licences are granted to the two new operators in 90 days.
The band has been used by Advanced Info Service Plc (AIS), which was granted a concession by the state-owned TOT Plc.
Since the concession ended on Sept 30 this year, the largest mobile operator was supposed to return the bandwidth to regulators but the deadline was extended to after the auction.
The National Broadcasting and Telecommunications Commission (NBTC) held an auction for two lots of 10MHz each of the spectrum on Dec 15. Jasmine International Plc and True Corporation were the winners.
To ensure seamless transition for existing users, the NBTC allowed the current subscribers to continue using the service until the auction's winners receive the licences.
This happens 90 days after they receive confirmation letters from the regulator. They are required to make the first payment within 30 days and submit bank guarantees in full or in instalments 60 days later, after which they will receive the licences.
AIS is encouraging its remaining 1 million GSM900 subscribers to switch to its 3G service on the 2100MHz band.
AIS users can check whether they are on the 900MHz band by dialling *727*[mobile number]# and then click send.
If they receive the message "This is an AIS number", they should take their handsets, SIMs and ID cards to AIS service shops so they can switch to the 2100MHz service.
The caveat is that if a subscriber uses a handset that supports only 900MHz and not 2100MHz, he will need a new phone and AIS is offering a handset exchange programme with some strings attached.
But if he insists on using the handset he needs to switch to True or Jasmine because AIS no longer has the band.
The users who get "This is an AIS 3G number" message don't need to do anything because they are already on the 2100MHz band.
The NBTC on Monday endorsed the winners of the 900MHz auction.
JAS Mobile Broadband Co Ltd, a subsidiary of Jasmine, and True Move H Universal Communication Co Ltd, a unit under True, will receive confirmation letters from the NBTC telling them to pay 50% of the starting price, or 8.04 billion baht each within 30 days. They must also submit collateral or bank guarantees for the remaining amount 60 days later.
The NBTC said although the winning prices at the auction are high, the 4G service fees operators may charge customers must be lower than the ongoing 3G rates. They must also have service packages for low-income earners and the handicapped.
Currently, operators charge 69-72 satang a minute for voice calls and 26 satang a megabyte for data usage.