So, I've got an iPhone 4S with an unlimited data plan

[zer0cool2011]

If I pop that sim (AT&T unlimited data plan) into my new iPad, which has the 3 Gig plan, will i be able to connect to the LTE network?

 

[GoCubsGo]

Try it and find out.

 

[DTxAg]

What you'll likely get is a nasty text message from AT&T shutting down your data plan until you call them.

 

[Epic Xbox Revie]

You'll only get 3G/ AT&T 4G (HSPA+)

 

[Stealthipad]

You likely will get data but not LTE.

 

[tytanic11]

Please let us know if this works.. I may exchange my wifi ipad for a 4G one if I can use my iPhone SIM

 

[blue43fan]

You likely will get data but not LTE.

Correct. If I'm not mistaken you would need an LTE capable SIM card. You would also have to change the APN.

I do know that you can definitely use an iPhone SIM in an iPad and use it for data, though. I've done it myself.

 

[ericrwalker]

I used a non-smartphone data plan with an iPhone for a couple of years. I had to change the APN settings in the phone to use the sim from my other phone. I would image that the APN settings are already set between the two though.

 

[DTxAg]

You can try it if you want, just let us know when AT&T does this:

https://forums.macrumors.com/threads/1115472/