Article 210.8 is what you are looking at. Assuming residential then if the refrigerator is within 6' of a sink then it must be gfci protected otherwise it does not as long as the receptacle is not on the counter
And, if this commercial (non-dwelling) and the refrigerator is in a Kitchen, 2017 NEC 210.8(B) requires GFCI protection no matter how far the frig is from the sink.