when is the appropriate age for a child to be left alone briefly?

[PeppyPiggy]

I'm asking because it's stormy weather outside and DD said she didn't want to go to the shop, my first thought was "okay, I'll be back in a second" just because she seems so mature, but I'm not going to do that... I feel sure that she is too young for this yet so I will drag her out with me in a minute. The shop is a Sainsburys literally directly opposite us, I can look out the window and see the offers on shelf (Chocolate Leibniz for £1... I can see this from my living room window that's how close we are). Sometimes when she is asleep at night and I realise I need something I find it frustrating that I'm looking right inside the shop yet am anchored into my house. I'm single, so no OH to stay in while I pop out, I have a friend over if I need to go out at all in the evenings or ask a mate to bring bits.

So when would be an appropriate age for a child to be left alone while mum pops into the shop across the road? I'm guessing like 8/9/10? What do you think?

I first walked to school on my own when I was 8 or 9 (without my brother), and often mum wouldn't be back from work until 5.

I remember she left me at home alone for the first time (to nip to the postbox, mind you) when I was 4. It was the daytime though.

I saw my dd attempt to do something dangerous in the kitchen a few days ago that I never would have expected her to try to do but it could have been awful if I were not there. So I can tell that for her at least, at this age, she's not safety savvy enough around the home yet or with emergency procedures. The thought crossed my mind but I remembered what she tried to do with the toaster and chucked that thought straight in the bin. Although weirdly enough I also do take the bins out without her and never even give it a second thought... gosh, hmmmm. I dragged her to the shops anyway and it became a puddle splashing fest which was great fun :)