Border Terrier crate to playpen switch

Moving a settled adult dog from a crate to a playpen is actually a smart call as they mature — they've earned a bit more space and freedom, and a well-chosen pen gives them that without losing the sense of having their own defined area. The transition tends to go smoothly when the dog already has a positive relationship with containment, which it sounds like yours does. To point you toward the right pen: what size is your Border Terrier, roughly — standard for the breed or on the stockier side — and are you mainly using this at home in one spot, or do you need it to move between rooms or travel?

That's the ideal situation to be switching from — a dog with no bad associations just outgrowing the snugness of a crate. For a 7kg Border Terrier in a fixed kitchen spot, you want something with decent height because BTs are natural climbers and jumpers, solid panelling rather than flimsy fabric, and a size that gives her room to stretch and turn without being so large it loses the den-like feeling she's used to. What's she currently using the crate for — sleeping overnight, or daytime downtime, or both?

Perfect — so this is really about giving her a comfortable, defined daytime space rather than strict overnight containment. My recommendation is the Ellie-Bo Heavy Duty Puppy Playpen, the 8-panel version in medium. It's steel construction so it won't flex or rattle if she tests it, the panels are tall enough that a terrier won't simply hop out, and it folds flat if you ever do need to move or store it. The 8-panel configuration gives you flexibility to shape it to your kitchen corner or wall. For a dog her size with her temperament, this will feel like a meaningful upgrade rather than just a bigger box.

Even with a confident, settled dog it's worth a short introduction — not because she'll struggle, but because you want her first association with the pen to be positive rather than just being shut in it on day one. Set it up a few days before you need to use it, put her existing crate bedding inside so it smells familiar, scatter a few treats in and leave the door open. Most crate-trained adult dogs walk themselves in within a day or two. Then close it for short stretches before you build up to the full four hours. You'll probably find she settles faster in the pen than she ever did in the crate because she has room to reposition properly.

You can swap it out completely if space is tight — she doesn't need both. But if the crate is somewhere out of the way and she still chooses to nap in it with the door open, there's no harm leaving it. Some dogs genuinely like having a smaller enclosed option available even when they have more space. If she ignores it for a few weeks once the pen is in place, that's your answer — you can store it or pass it on.