Instructions
Block your cat's access to the space under the couch. Use pieces of wood, bolsters of cloth or even duct tape to block the opening. While it may be unsightly, it will keep your cat out and once it adopts a new hiding or exploring space through training, you can try removing the blockers.
Make the space under the couch undesirable to the cat. For example, place a nubby plastic runner with the nubs up under the couch. Your cat won't like the texture and may stop going under there. Alternatively, try sticky tape with the sticky side up.
Provide an alternative space for your cat to explore or hide. Cat carriers and cat tubes are some alternatives. Train your cat to feel safe in the carrier or tube by gradually introducing it to your cat. Place treats inside the carrier or tube or spray them with catnip to entice your cat. Reward your cat with tasty treats such as diced tuna or chicken whenever it goes into the alternative space.
Determine if your cat is going under the couch due to anxiety. Figuring out the cause of the anxiety will help to stop your cat from going under the couch. For example, some cats hide under the couch when visitors come over. Try blocking your cat's access to the space when you are expecting company and provide an alternate space. Reward your cat with treats for going to the other space.
How to Keep Cats From Going Under the Couch
Cats like to explore small spaces. Others like small places to hide when scared or anxious. Either way, the space under the couch is appealing to cats. Stopping a cat from going under the couch means either blocking the cat's access to space, placing a deterrent in the space, providing an alternative hiding space and/or training. Many people believe cats cannot be trained but cats do respond to reinforcement training. Reinforcement training utilizes tasty treats to reward desirable behaviors.