I'd say tip the lot out into your garden waste bin and clean the pots out before refilling with fresh compost - not forgetting crocks or a layer of gravel in the bases for drainage. The compost in the pots won't have any nutrients left, and may well be full of weed seeds.

Agreed. Your plants will thank you for it.

I take all my pots to the tip and empty them straight out save filling garden bags then wash them out using jayes fluid nice clean start for spring

I concede the point about weed seeds, but I thought that spent compost was quite useful in relatively small amounts as a soil conditioner - we have a lot of heavy clay, and it does seem to help. We have lazy, selfish neighbours, so our soil is full of wind-borne weed seeds anyway. Cut out that bit about lazy, selfish neighbours - he's ninety and I'm being uncharitable, but it doesn't help with the weeds. Make sure if you do decide to put it on the garden that you root out all the big, fat beetle grubs that may be lurking there. If it's just plain common or garden soil, lose it!

I used to tip mine out onto the garden, before I got wise to the fact that I was incorporating more weeds into the garden therefore making extra work in the springtime, now it goes in my compost bins and gets turned around for a couple of years before going onto the garden, I admit I still get weeds, just not as many..