I've been trapping on my property for years using various cage traps, the largest of which are single door and double door 12 X 12 X 36" Havaharts. I've caught plenty of opossum and raccoons, but I've never ever been able to catch a grey fox in any of my traps. I know they are there as I've seen them many times on my cams. In fact, I just watched one take a stroll past one of my traps tonight ....I use commercial bait/lure (for foxes and canines) and meat (kitchen) scraps and sometimes I'll throw some raw squirrel meat in the traps. But so far I've never been able to catch one, despite them being regular visitors.
What might I be doing wrong? What sort of bait/lure is the best to use? Any advice?
Just to add, this is a semi-rural area with farms and residential homes, and I've seen fox tracks right outside my back door in the snow so they seem unafraid of being around human habitations.

Maybe a larger trap or a sweet bait. Or cover floor with grass clippings or sifted dirt. Or cover bait and use a drop or two of lure.

I'm not an authority on Cage Trapping Greys. I accidentally catch one or two Grey's a season (in Williams Trap). This is at the back of our property when I am removing Possums, Coons & Skunks and avoid catching our kitty cat.
I am using Mini Marshmallows for bait. Then Hassel & Greathel bait into a depression in ground, under floor, just behind pan.



A good rule for baiting- Place bait (jackpot) under the trap, just behind but close to the pan. Just make a depression with toe or heal of boot or dig with small shovel.

Cages for canines is a lower percent game than footholds. Foxes, red and grey, can be caged coyotes not so much.

As said a larger cage helps. Taller more important than width. Basically don't try to squeeze them into a small confined space, they'll balk at that. Don't be stingy with the bait. Give them a reason to throw caution to the wind. Tempt them with a taste by trailing some into the cage. Position the cage so going in the front door is the most obvious and simple route and they don't get frustrated trying the back of the cage or making laps around it.

I would recommend more of a bobcat style cage trap. They are tall traps so you're not forcing them to duck and they are on the skinnier side. Plenty of them out there, Mercer here makes good ones, Norm Blackwell has a good one, and many more I can't recall atm

Try an egg for bait/visual.

Hern gives you very good advice. Sweet fruity, musky odors and some eye appeal work well. Adding some camo to the cage with branches, limbs etc. Will help the presentation. If you have any grey fox gland that certainly helps seal the deal.

In some cases, a good cleaning of your cage with a pressure washer and scrub brush can remove other captured animal odors. There can be lots of odor from feces, urine and hair. Mostly the sides and bottom of the cage. I have seen refusals many times due to a contaminated cage that some animals won't want to enter the trap for that reason.

Bacon fat mixed with caster. It's like crack

Thanks for the advice to everyone who replied. One more thing - can anyone suggest suppliers of some of these taller and bobcat-style traps?

I know Murray's Trap supplies carries the Blackwell trap. Not sure what retailers sell the others

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Give them something to focus on, I've caught many a coon with a feather hanging in the back of a cage.

Fruit based baits are one of the most overlooked canine baits. Everyone goes for meat based but canines probably eat as much fruit as they do meat when it's in season. I've seen greys on game camera photos up in a pear tree picking off pears. Coyotes under the same tree eating dropped pears.

WCS Treeberry has caught more than a few for me. June's Widowmaker persimmon is another good one.

cat Trapper are you saying bacon fat, or bacon grease ? How much of each ?

You are using the wrong kind of trap for fox.
Cages and bodygrips will only catch the odd fox,most likely a pup.
You need to utilize footholds or snares(set to hold live or set to dispatch).
Those will catch every one if set properly.

Bacon grease. I never messure out how much of each. Just enough caster that you can smell it. I dont think its possible to over do it. Works like a charm. I've caught fox in some pretty small cages, but we also have a ton of Grey fox. They dont seem to be shy of much around here. I caught one on a set a peed next to with an exposed trap. The main thing is something to get their intrest. Since it's a cage trap and rolling will only help you, figure out where you are going to put the cage but before you place the cage, dig a hole where the back of the cage will be and put something skunky. Then place your cage on top. I would do the same with the bacon grease/caster bait instead of the skunk.

You must not have a lot of fox to catch. We catch them in cages and DP’s set for coon. Nothing but an egg in the cages and dry cat food in the DP’s. Heck, even catch bobcats in the cages from time to time.
Don’t overdo it. A normal store bought egg gives out an odor and is extremely visible.

Red fox are really hard to get in a live trap. Grey fox on the other hand I have caught many in coon cage live traps and body grip traps. In fact I have never caught a red fox in a live trap except a mange Red Fox that was not thinking right. Grey fox are even easier to catch in a foothold then a Red Fox as I would catch them as kid in raccoon sets.

Schrecken13 Not sure if you get snow, if you do your job will be really easy as you can set were you see him travel for sure. Looking forward to seeing your post with your catch my friend.