He may not have been used to eating hay ever. Some buns never get hay when they’re little, and they can be difficult to get started on hay.
Is he eating his other food? How is his poop looking? (A new bun could be a little stressed out from coming into a whole new household and appetite might suffer.)

I serve hay in small wads once in the morning, once at night. if I give my buns a big bunch of hay they eat a little and then decide the rest is “old”. (I still let them have a bit of “old” hay so they can have a nibble 24/7 as they should be able to.) It took me quite some time to find a hay that my buns ate with any kind of good appetite. Rabbits can be really picky about hay. Some like soft hay, others like coarse hay. Mine like leafy hay (third cut).

Sometimes a bun will eat hay if you hand feed it strand by strand for starters, then they sort of develop a taste for it.

Hello and welcome to Binky Bunny! If your rabbit is an adult, you should cut back on the amount of pellets you are giving him, which will hopefully force him to eat hay. Try different brands and varieties of hay to entice him. Some rabbits don’t like timothy, but they do like orchard grass, which is sweeter. Or they like a softer hay, such as second cutting timothy. American Pet Diner Gold is a second cutting of timothy and my rabbits have always liked it, along with a variety of other hay. There is also meadow hay, oat hay, botanical hay, blue grass hay. If he is a young rabbit, he can have alfalfa hay. Most rabbits love that. If he is an adult, you could get a small bag of alfalfa and sprinkle a tiny bit on the timothy or other hay to see if the intense aroma of alfalfa will get him interested.

There are also hay toppers that you can sprinkle on top of the hay.  They are edible flowers and herbs.  The BB store sells it, but they are sold out right now.

So glad you adopted him!

Oxbow Hay Company makes a blend of hay called “botanical mix”. In addition to Timothy Hay, it also has some dried lavender, chamomile, clover, and lemon balm blended in. In my experience, this has been a good hay to reach for for buns who are “hay snobs” or those rabbits who are being acutely picky due to medical issues. The fragrance might be more enticing, and may help him start to at least try to eat some hay.

I am BY NO MEANS and expert, and am offering this tip from my personal experience only.

I am no expert, as I’ve only had one rabbit and I’ve had him since last August, but he also does not eat Hay. I have tried different brands of Timothy hay and he won’t eat it. He eats the pellets, and I let him have as much as he wants, but what I feed him twice a day is Kale. This is kind of pricey, but if you can afford it, try it out. Our Safeway sells this bag of chopped up organic kale for $5. It’s perfect for him. He probably eats one bag a week or a bit more. He’s an 8 lb rabbit. I just toss him a handful in the morning and evening. He loves it. 

He eats other greens from our garden too (leaves of broccoli, cauliflower, etc), when we have them available. Right now is end of their season, so he’s been getting a lot of cruciferous (?) leaves. 🙂