Please can you look at this picture?

[BertrandRussell]

And tell me whether she looks overweight or not?

Oh phew- Mabel is 8.2kg. But she looks huge compared to yours!

Wow my BT is 9kg but she does seem taller than other BTs I know, and she isn't pedigree.
She needs stripping though.

Here's a useful condition score chart
www.wsava.org/sites/default/files/Body%20condition%20score%20chart%20dogs.pdf
She looks a bit over - should have a defined tuck to her abdomen and a 'waist' from above

She does have a waist- and dp can "span" her chest.(he does have quite big hands though!) Oh, I'm getting all confused now.....

She doesn't look massively overweight but she does look like she could do with trimming down a bit.

Most border terriers I see are on the tubby side so ones that aren't do look skinny.

It is very very easy to get a dog to the right weight though - you're in complete control of her calorie intake so if you drop the amount she's getting gradually she WILL lose weight. Thankfully dogs don't have the same issues with food and weight as humans so you don't have to deal with all the psychological barriers to weight loss that we do

I would say from the pic taken from above, which is the best way to assess dog weight, that she looks a little over weight. I keep my dogs trim with a well defined waist. Vets always comment on what a perfect weight they are yet other folk at the park etc.. will say they are too skinny.

I would try reducing her food by just a little bit. Don't do anything drastic. Just a little bit and see how that has gone say in 1-2 months. She's not at any kind of size where you need to rush the process, just a little weigh loss at a nice sensible speed to trim that waist a little. Or if you are unhappy with reducing food even a little bit, add 10-15 mins extra exercise a day or something