How can i check if my SG3 is locked to a network ?

[Alanp97]

Okay so i bought my phone off a guy from town (2nd hand) I cant put my sim in till the morning when i cut my sim to make it a micro sim. I had the samsung galaxy ace 2 so it used a normal sim. I live in ireland so the main networks are Meteor and vodafone lets just say. When i look at the homescreen ( this is without a sim in the phone ) it has a vodafone display showing its top apps and stuff like that. My sim is with meteor. So does this mean it will be locked to vodafone even when i put my sim in ? Is there a way of checking that its locked or unlocked ?