Wood chips to improve soil?

I could just leave it in a heap and use it once it has broken down?

IMO opinion, this is the best option - I think you'll be surprised at how long it takes to start rotting

The best thing of all if you can locate a source is horse bedding/horse-muck mixture where the bedding is wood shavings. Worked wonders on our clay soil. You just barrow it on to the soil in autumn and dig it in the following year. We are OK as it's our own animals but you need to make sure that the animals haven't been fed any dangerous veterinary medicines

Totally agree apart from "barrow it" - should be "barrow it, barrow it, barrow it etc." it needs a lot but does work wonders in lightening up the soil as well as raising the bed so that it drains better.

Whenever a bed is empty, cover with home made compost and or manure laid down first then wet paper or cardboard then a good few inches of woodchips. and leave for a few months
That's what i do now. I have stopped digging and my heavy clay garden has slowly improved.
But, it is a slow process and a lot of gardeners expect instant results so allow a couple of years to get the soil back in balance.
There are lots of UK gardeners using the woodchip or Back to Eden method so a quick u-tube search will be beneficial.

Thanks for all the replies, especially the heads up about the Eden Method.

I laid some woodchip paths last year on membrane, I was surprised today to see how much had rotted down.

In that case you could use the rotted chips on your borders & put the fresh on your paths 😊

Could it be you are actually based in Nettlebed?  Cheers,  Tony.