Which fence belongs to me when i look out of a window at the rear of my house onto my back garden? please help

Its the right side
I know coz we've been arguing with the neighbours that they need to get a new fence.And my fella will only pay for the right side and wants the neighbours to pay for the left.
The fence that has the posts facing you.
its to the left of you
If the fence posts are in your garden then the fence belongs to you.
It will be the left.
It depends on where the property line lies and who built the fence. The part about the fence posts facing you isn't true. That's just a design issue and has nothing to do with ownership. Most fences are not built exactly on the property line; they're on one side or the other. So (if you live in the US) check the public records for your county for any building permits that may have been filed regarding the fence or ask your neighbors if they know who owns the fences. If there's no public record about the fences, you may need to hire a surveyor to determine which side of the property line the fence is on. Sometimes homeowners cooperate and share the expense and ownership of a fence.
Listen to fyrfly, s/he's correct.
The one you paid for.
The right hand side looking out of your back window
if you are in the uk, its the right. but if you want your own fence with the posts facing the way you like, then place it INSIDE your garden, then you can have your own fence both sides... i did this cos my lot wanted chicken wire waist height ( I DONT THINK SO !! )
If you get a detailed plan of your land, check all the measurements and the like, if the fence is within your boundaries then the fence belongs to you.
you will have to know where your property lines are.a survey probably was done when you purchased the house. This can get sticky because if the neighbor originally built the fence, but it is on your property and you decide to tear down/modify the fence you may really tick off the neighbors even though the fence is actually on your property. :) Best thing is: find out where the property line actually is, even if you have to contact a surveyor, talk with your neighbor and go from there.
you can only be sure by looking at the deeds, they should have that information on plans.

generally if there is a fence that has the posts on one side or another, you would install it with the posts on your side, but many fences are of the panel type and the posts are in the middle.

You cannot guarantee that fences that have been installed prior to your occupation have been done in that manner.

Your neighbour in the past may have installed a fence on his side of the boundary, in which case your garden is a bit bigger!
The old rule was that if you erect a fence then the nails should face your property IE the heads are on your neighbours side and the points face your property. this generally puts the better and more appealing side on your neighbours side. Hard to bear but that is the law.
Normally the fence on your right looking from the house towards the rear. The only point is that the rear fence may also belong to you. The best way to check is to go to the local council offices and request to look at the plans of your area. You will see either a Red line of Thicker marked line against your property this indicates that the fence against this line is owned by you and is your responsibility. You can also check with the council, if you require a fence and if so the minimum height they require. All the best
i was told by the land registry that stood outside at the front of your property your boundary fence is on the left so i would think that it would follow through to the back and it will be on the left as well.i maintain my fence to the left and so do my neighbours so it must be the left.
Fyrfly is right.
If you rent the property ask your land lord. If you own it, look on your deeds, it varies with different properties.
I have been here and the only way you will know for sure is if it's indicated on your deeds. Don't bother with the council in the U.K. as they will not want to know. When I phoned them I had several different answers from the one department. If it is not indicated on your deeds as I was informed by my solicitor then you are both liable for the fence, that is you share responsibility.
Check your legal documents to find out
looking out from your house the one on the left and at end of garden.
Nor the one on the left but in my case it's all of them even though I am semi detached best bet is to ask the solicitor