Ideally, you need to cut back Forsythia after flowering in spring. If you cut them back now, you'll cut all the flowers buds off.

Of course, if you absolutely have to cut it back...if it's blocking a path or scratching the car, then yes, hack it back

Thanks,no it is not causing an obstruction but whilst it is bare,it is so much easier to see where I am cutting...just had a look and ,yes,there are buds starting to form...surely it is too early or is it the weather causing the garden to be all out of sync????

No, it should be starting to put buds out now ready for flowering in Spring.

You will find that as soon as the flowers die, the leaves will start to grow (April ish) so cut it back then and you won't lose the lovely flowers

If you wait late February you can cut some then and bring the branches into the house and the flowers will open weeks before the open outside. I've even brought some in at Christmas , to open after the decorations come down.

Thank you very much,that has been good advice which I shall follow.

My forsythia is now losing its flowers,but is full of leaves,inspite of this,can I prune it now?
Thanx

Yes you can, its the right time. Cut off the parts that have flowered while you can still see which they are but leave the branches that grew last year as they will flower next spring. If you want to reduce the size without losing all the flowers you could do it over two years, half now and half next year. It will look a bit odd for a year - depends whether you want symmetry or flowers. I reckon a forsythia that doesn't flower is rather a waste of space!

Thank you,definately prefer flowers,rather a dull bush without.