Afternoon tea, says nanette, is a light afternoon offering of tea with cakes, sandwiches, and scones. High tea, on the other hand, is more elaborate, "usually featuring a small warm dish along with all the afternoon tea trimmings," says nanette. "It tends to be enjoyed toward the end of tea hours." pikawicca agrees in principle: "Afternoon tea is tea served with finger sandwiches and small cakes, typically around 4 p.m. High tea is working-class terminology for dinner," says pikawicca.
PhilD disagrees. High tea is a tradition that was once common in the UK, but it's rare to find it offered today at establishments that don't cater to tourists. "In better-off families high tea was the meal served in late afternoon/early evening before the children went to bed," says PhilD. "It usually had a selection of cold cuts and salad followed by cakes, but no hot dishes (apart from crumpets and tea cakes)." Working-class folks would simply refer to the evening meal as "tea" or "supper," what Americans would call "dinner." As for high tea, "in the ’60s it was only my grandparents (who were from London) who still served it, and they were born in the 1800s," says PhilD.
Discuss: High Tea vs Afternoon Tea?