Consulting firms always provide a phone. For all offices. They do it because you need one as a consultant, and it can't be yours, as it needs to have some safety features. It's also a status thing. Not only you will have one, most likely you will have a good one (not necessary the ultimate model, but something good).

Hi there,

First, yes, they should definitely offer a phone.

Second, when it comes to things like this, just ask them - you're part of the company now!

Hello!

I am a million percent sure they will offer you one, it becomes an extension of yourself. 

Cheers, 

Clara

They'll most likely a) provide you with a mobile phone (in most cases), or b) support by covering cost of your personal plan at least. Given it's OW, I'm pretty sure a) holds true, as latter is only common for select small / boutique firms.

In any case, don't be shy to ask them about the specific arrangement upfront. 

Yes, you will definitely get a phone. You can usually use the phone privately as well.