Sooo the title says it all!
The iPhone5 like all iPhones will connect to the network available.
If in an area without LTE coverage, it will automatically connect to 3G or EDGE, whichever is available.
If your question is about whether an iPhone5 without the LTE antenna is available, no it is not.
Actually, there is a model with a slightly smaller screen, a glass back instead of aluminum, and a slower processor... It's called an iPhone 4S
Seriously... If the OP is asking about the 'service plan' as opposed to the phone, that's entirely up to the carrier.
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