Your side, yes, of course - but if it's going to affect them, it would be only polite to have a word first... Obviously you can't paint their side of it without their permission.

The only situation where you might not be able to paint it exactly the colour you want would be if you are in a Conservation Area, live in a Grade I or 2 Listed Building, or if you are in the curtilage of an historic building of some kind.
If it's none of these, it's just courtesy to tell your neighbours.

All you have to do is say to them that you are painting your side of the fence, so that they are warned in case any paint dribbles through the slats

Yes that happens Hijuju and then they paint it another colour and it dribbles down yours! Good neighbours are much better than painted fences ask them and come to an understanding!!!

It actually depends whether it is your fence or their fence. Are the fence posts on your side of the fence? If so it is yours if not it is your neighbour's fence. Obviously if it is your you can paint but good manners requires you to let your neighbour know. If it is your neighbour's fence you really need to ask permission first - and if they have any sense they will say yes.

Why that MG?

We put up our back fence years ago as their alsatian dogs were jumping over and going walkies and their business. We didn't argue, but got permish off him for 7 feet. Recently they sprayed it what I called 'yukky brown' and as ours was yukky neglected, I didn't mind the run throughs....he didn't ask. So this weekend we sprayed our side green welly green, second coat.....we didn't ask either....touche.

Drc not sure what it is you are asking.

Hi MG Modern stuff like sprayable fence stuff creates new situations... No etiquette for it MG. Force of spray sends though gaps.... they didn't ask...so we didn't.....probably too long winded first time MG. It's a long way round the block to go to ask!!!!!!

Dorjac I understod what you were saying. Drc asked 'Why that MG' and I wasn't sure what he was referring to. My saying you can't paint a fence if it isn't yours or something else.

I wondered why you said this 'If it is your neighbour's fence you really need to ask permission first - and if they have any sense they will say yes' and Im a 'she'

You could always change your name to 'Denis'....LOL.

Ah, firstly apologies Drc for calling you 'he' not always obvious which sex someone is without a photo of the person. Let me rephrase my response... If our neighbour came and said I'd like to paint our side of your fence Bulba and I would automatically say - 'sure go ahead - in fact perhaps we can do the whole thing in a oner, save on buying two lots of paint'. Living in a rural community we all make sure that anything that will affect our neighbours we advise them of, good manners. I've spent the last week apologising to our neighbours as the workman we had putting down a new flat roof played Radio 1, or the local pop radio station, loudly from 08:30 until 20:30... nearly drove me insane! Another example, we would not think of using a noisy piece of garden equipment before 10:00 on a Sunday because we know one of our neighbour's like a long lie... All helps to smooth the wheels of rural living.

I sympathise about the noise pollution, with Radio 1 and noisy garden equipment.
Although we live in a wonderfully remote rural position, there's that damn nightingale singing all day and night too and noisy frogs croaking!
(lol.... actually we don't escape and the worst thing is low flying jet aircraft when the French air force practise low flying over the nearby lake! So nowhere is perfect!)

Bertie we used to live in the middle of nowhere in Aberdeenshire and had to contend with the RAF using our dirt track as a bombing run. They scared our then 3 year old son and his 4 year old friend so badly one year the friend would not go outside for weeks. Did the RAF apologise? Did it flip!