Sometimes it's difficult to tell. Allergy symptoms typically include sneezing, runny nose, nasal and sinus congestion, sinus headache, fatigue and itching of the eyes.
Cold symptoms are due to virus infections.
Cold viruses produce symptoms of runny nose, sinus congestion and headache and may also be associated with occasional fever, chills and muscle aches. However, viruses do not produce itching symptoms at all. In short, allergy does not produce fever and colds do not produce itching. Frequent symptoms of hay fever include itching of the eyes, sneezing, itching of the roof of the mouth, nasal congestion, sinus headaches and fatigue. Airborne pollen and mold spores are common causes of seasonal hay fever symptoms.