I've got two indoor cats and I've been trimming their nails since we got them. They use their scratch posts heavily so I only do a little tidy up now and then. One loves it and lets me do a full pedicure on his front paws including cleaning any dirt (they go outside on a harness), removing any bits that have been flaking and then rubbing each claw with an antibacterial wipe once I'm done with the actual clipping. The other is a bit too interested in the clippers and is always trying to lick them which is a pain but at least they don't mind being clipped

It's not a different rule, but think about the different surfaces that cats come into contact with if they are indoor or outdoor.
Outdoors cats will walk on concrete and pavement, which will naturally keep the claws trimmed, as will bricks and trees etc.
Indoor cats do not have these surfaces to naturally keep the claws in check.

Scratching posts are not intended to keep the claws short. They are there to sharpen them and to fulfill natural scratch instincts, and also to get rid of the claw sheaths. Scratch posts will make the claws sharper rather than duller and shorter.

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we trim Alfies, always have done. He's an indoor cat and has various scratching posts but claws still grow and get sharp... very noticable on laminate flooring!!! we tend to do it every coupld of weeks or once we hear him starting to clack across the floor!!!!

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I trimmed our kittens' claws for the first time at the weekend. It's now much nicer when they climb up your legs!

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Bonnie and the gang xxx

I've never trimmed mine but have previously found that Oska and Sassie our two elderly persians in the last year or so their claws have got very thick and they have needed trimming else they would of cut into their pads. Sassie who is the tiniest little thing really objected to this when she had hers done at the vets a few weeks ago. Our vet normally does Oska's FOC when he has his B12 jab and we asked him to do the same when Sassie had hers. She drew lots of Brian's blood!!!!

Scamps an outdoor cat during the summer anyway, he doesn't go out much winter time, I have never had to trim his I think our silver birch takes care of that

I have 1 out door cat which I dont trim, the other 2 are indoor cats and therefore trim them when ever they need it also just before a show.

I have no problems, both cats happy to comply

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the scratching post actually sharpens claws as it helps strip old sheathes off the claws