The iPhone 5S will be available September 20 at AT&T, Sprint, Verizon and T-Mobile. Which carrier will most people choose this year with their iPhone 5S?

On September 20, Apple will be releasing the new iPhone 5S to four major carriers in the US, namely AT&T, Sprint, Verizon and T-Mobile. The higher end version of the iPhone will not be available for pre-order.

AT&T, Sprint and Verizon are offering the iPhone 5S with a wireless service plan. The price of the handset starts at $199 for the 16GB model. The 32GB model price starts at $299 while the 64GB model of the iPhone 5S has a starting price of $399.

The iPhone 5S will also be available contract free and unlocked through T-Mobile. T-Mobile is offering the handset at $649 for the 16GB model, $749 for the 32GB model and $849 for the 64GB model.

Buyers of the unlocked and contract free handset will be receiving the iPhone 5S A1533 (GSM) model. The handset will come with a nano SIM card which is already installed on the device. SIM activation can be done by visiting any Apple store or any T-Mobile store. SIMs can also be activated through phone call by contacting T-Mobile. International users will have to secure nano SIM cards from local GSM carriers.

With four major carriers adding the iPhone 5S to their offerings, it can be difficult to decide which carrier to choose. A poll from last year revealed that most people went with AT&T with their iPhone 5 handsets.

The top second choice was Verizon while the third spot was taken by Sprint. The iPhone 5 was made available for prepaid use through Cricket -- which landed the last spot among the 4 carriers. Rumor has it that an iPhone 5S U.S. Cellular is also on its way. However, Apple's "where to buy" page only lists AT&T, Sprint, Verizon and T-Mobile to date -- with no mention of U.S. Cellular. It may be that the U.S. Cellular iPhone 5 will be available at a much later date.