Mine took one day. I'm not exaggerating! It sounds awful but when I got his indoor run I let him wee on the carpet so I knew where he would go then I put a toilet there with woodshavings in along with a few of his poos from his cage and some of the wet woodshavings from his cage too. I watched him sniff at it and straight away he knew to go there and has never dirtied anywhere else (except for when he was poorly and drugged up so I can forgive that!) I think as long as you know where they want to go and you use some of their waste so they get the idea then rabbits are pretty quick learners as they like to stay clean.
My second rabbit will poo on the floor but mostly wees and poos in the toilet.
I also have their hay in their toilet with them otherwise they go toilet anywhere!
Good luck!
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