Grooming
The Field Spaniel needs more grooming, daily brushing, where the English Springer Spaniel needs brushing a few times a week.
Temperament
They differ most on independence (English Springer Spaniel: keen to work with you; Field Spaniel: cooperative, with its own ideas) and on intelligence (English Springer Spaniel: needs daily brain work; Field Spaniel: learns readily, likes games).
Alike
They are much the same size as adults, about 22 kg (48 lb) for the English Springer Spaniel and 22 kg (47 lb) for the Field Spaniel.
Alike
Both are rated the same on affection: a lap or leaning dog.