Well acers are deciduous, and it is autumn, so it's not unexpected if it is.

Here in West London though, the Acers in my gardens are not yet losing their leaves. If you're in a colder part of the country, I guess they could be dropping already though. Unless your plant is in a pot and potbound, or dried out at some point.

One of mine did earlier, it got a nasty bout of 'east wind-itis' and dropped all its leaves in protest. The other two are still leafy. I'm in West Somerset.

In Cornwall we had some strong wind about 6 weeks ago and my sycamores (also acers, but not very decorative) lost about 80% of their leaves. They just turned brown & dropped off very early.

Mine have all but gone - NE Scotland.

Ours are still changing colour and dropping at the same time.

Mixed bag in east Scotland - established Acers in sheltered spots are still in full leaf, those in windy conditions in my garden are bare and have been for a few weeks (much earlier than last year - especially for garnet ones)

mine still holding leaves, but they have got a touch of wind burn, so expect them to drop anytime soon,also been exceptionally dry this year??

One of my Acers has dropped all it's leaves, but it is not in a very sheltered spot. The rest are quiet happy, I live in the north west.

All leaves on- all green - but then I am in Spain and the sun is set to blaze for the next week. ;o)

I'm in Leigh-on-Sea, some of mine have drop their leaves but some are hanging on to their's but not for much longer I expect, then in the spring the buds will produce new leaves, it the cycle of them. :o))