The handset - dubbed the "iPhone killer" because of its high-tech features - has a retail price of Dh2,499 in the UAE.
But it is being offered for free on at least two of Etisalat's price packages, as the business model of subsidising mobile handsets grows more popular in the region.
Rival operator du is offering the phone with a discounted data bundle, according to information on its website.
Etisalat said today it will offer the Galaxy SIII phone for free to subscribers to its 4 gigabyte (GB) data package, which costs Dh449 a month and includes 800 local minutes and 200 free SMS.
Under a different offer, Etisalat says it will sell the Galaxy SIII phone for Dh2,499, and offer a 500 megabyte data package free for three months. It said it would launch plans for its prepaid customers "soon".
Corporate customers would also be able to receive the device for free under one of its price plans, Etisalat said.
Du is selling the phone for Dh2,499, and offering 2GB of data per month for the price of a 1GB package.
Samsung told The National earlier this month that the practice of subsidising mobile handsets - as Etisalat is doing - marks a growing business model in the Gulf region.
"I see the operators as the drivers for the mobile-phone business in the future," said Ashraf Fawakherji, the general manager of the telecoms group at Samsung Gulf Electronics. "They will be influencing the market much [more]."
The Galaxy SIII phone has a 4.8-inch display and can track its user's eye movements to ensure the screen does not dim or turn off when in use.
It is expected to be the main rival to Apple's iPhone 5, which is rumoured to be going on sale in the third quarter.
Several retailers in UAE said they have already sold out of the SIII, and Samsung has acknowledged it will be unable to meet the initial demand for the device.
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