Anxiety
It could be the case that something has caused your cat to start becoming anxious. A cat might be anxious because it is in an unfamiliar place, it is around new people, there is a lot of noise, or there are other animals present.
Stress
It might also be the case that your cat has been doing it due to something causing your cat to be stressed. This would be more likely if your cat has started doing it since something happened that might cause your cat to be stressed.
A cat might be stressed because of a change in its routine, because it is not getting enough attention, because it is not getting enough exercise, because it is not getting enough playtime, or because it is not getting enough food.
Illness
It could also be the case that your cat has gotten an illness. This would be more likely if your cat has been showing other signs of illness such as being lethargic or peeing in other parts of the house. If it seems like illness could be the reason, the best option would be to take your cat to a vet.
Unable to access litter box
It could also be the case that your cat no longer is able to access the litter box. If your cat is not able to access a litter box, it would help to make sure that your cat can.
Dirty litter box
Another possible reason is that the litter box is dirty. It would help to try cleaning the litter box.
Marking territory
It could also be the case that your cat has been marking its territory by peeing on the couch. This would be more likely if your cat actually sprays on the couch instead of urinating a lot. This would also be more likely if the behavior has started since you introduced a new pet into the house.
Consider what else happened when your cat started peeing on the couch
To help figure out the main reason why your cat has been peeing on the couch, it would help to consider what else happened when your cat first started doing it. If it started doing it when you got a new pet, the cause would be more likely to be due to marking territory or anxiety. Whereas, if your cat started showing other signs of illness, it would be more likely to be due to an illness.
How to get my cat to stop peeing on the couch?
Below are options you have when dealing with the behavior.
Take your cat for a checkup
If you are unable to figure out why your cat has been doing it, the best option would be to take your cat for a checkup with the vet. By doing so, you should be able to find out if illness is the cause and get expert help tailored towards your particular cat.
Ensure your cat has access to a clean litter box
It would also help to make sure that your cat has access to a clean litter box.
Limit reasons why your cat might be anxious
It would also help to limit possible reasons why your cat might be anxious. Ways of doing so can include giving your cat access to a different part of the house where other pets can’t get to.