It is important to take care of an overgrown beak, which can interfere with the budgie being able to eat. Unfortunately, it is not safe to trim your budgie’s beak yourself. There are many nerves and blood vessels in the beak. An avian vet is the best person to take your budgie to. An avian vet can also determine if the cause of the overgrown beak is due to a health problem or deficiency. You can try using http://aav.org/search/index.php to look up an avian vet in your area. If you don’t have an avian vet in your area, try to find someone who can do it for you who has experience and knows what they are doing. Try local vet clinics or birds stores.
After you have the beak trimming done, you should provide your budgie with a chew toy, which will help prevent this problem from recurring. Chewing is how budgies keep their beaks in shape. A cuttle bone is important for calcium and minerals but is much too soft for keeping the beak in shape. Most pet stores sell toys that are made for birds to chew up. Just remember that because their beaks are smaller and softer than parrots, budgies need a softer material to chew. So toys made of popsicle sticks or soft wood would be good, but ones made of manzanita sticks would not. You can even make your own by hanging paper towel or toilet paper tubes in the cage. Pet budgies should always have a toy or item in the cage that is meant to be destroyed, so keep in mind that such a toy would need to be replaced every once in a while.
An excellent chew toy for budgies is toy called the Bird Kabob, sold at many pet stores, that is made of soft wood that is perfect for budgies to chew up. See the photo on the right of the Bird Kabob that still has two of the pieces of the soft wood on it. You can take the individual pieces off and attach them in the cage where the budgies like to hang out. The chewed wood can get messy so I recommend using a cage skirt if you attach it directly to the side of the cage.