I don't think healthy beaks normally need trimming.

As long as you have some sort of rougher perch for them to rub their beak on and lots of different toys to chew (like wood) they should remain a healthy length.

At for months old it shouldn't be that long... but if you're concerned you could always have it checked out by an avian vet... have you taken him for his first 'baby checkup?' yet?
Long beaks don't really cause health problems, but health problems (i.e. liver disease) cause long beaks.

Hope that helps!