Won't do a poo on the toilet

Laura

My son is 3 at the end of November he has been toilet training since July. He has gotten the hang of wees and has started telling me that he needs to go and is fairly dry at night too.

He has yet to do a poo in the toilet he does it in his pants and tells me after. He usually holds poos in until we get home he has only ever done 1 in public.

How do I get him to poo on the toilet?

How long did your kids take to do poos on the toilet?