What age can kids be left at home after school?

If he's ok with it and you trust him
No to do anything reckless then I'd say it was fine.

11 year olds start high school and the majority of high school kids I know walk on their own and across busy roads. So I'd say it's fine.

Fine.
Just make sure you provide written contact details for assistance should he need it.
Talk to him about possible scenarios that may happen and ask what he thinks he would do.
Perhaps have a code word for you all?
In case someone from school (or not) tells him they know you and you've said he's to go with them. No code word, no go.
Obi keep the code secret......

Kind of OK... but it is putting a lot on the 14 year old - what if she wants to stop off at a friend's house, stay for an after school club, what about GCSE year and any after school revision? Would try to make sure she doesn't feel hard done by.

(I was in her position and resented it for years after)

My concern would be for the 14 year old who would be obliged to come straight home after school every day for the next year or so.

How about a compromise? Childminder twice per week and 14 year old the other three times. Childminders cost money as you say, but it's only until secondary school, at which point he'll be more independent.

My 10 year old would easily stay at home for hours (and also did so whem she wass younger). same question on MN every so often with completely opposite views

Depends on your 10yo.
My just 11yo has been coming home alone since Easter yr 4, mostly I've been here and older brother gets back about the same time.
Sometimes I don't get back till about 4.30, sometimes ds1 goes to a club, sometimes ds1 goes out after getting home.

I'd say totally fine

Fine as long as the kids are comfortable with it and you talk about 'rules' or what to do in emergency etc. Also single parent and my child has been coming home alone since she was 10 (when she started secondary school). It sounds dreadful but she could call me at any time and tbh comes in and does her homework and despite not being my ideal scenario it really isn't an issue.

I think it's fine for the 10yo but it is putting quite a lot on the 14yo. Like PPs have said, what if she wants to go round to a friend's or to an after-school club or something? Or has detention? She would feel pressured to come home which isn't really fair on her.

Could you maybe get a childminder for him 1 or 2 days so she can do stuff if she wants? Or even organise playdates? Find out which days she is most likely to be busy.

I think 10 is definitely old enough to walk that short distance and be at home for a short while. Make sure he knows what he is/isn't allowed to do and has a way to contact you, his sister and someone local who could pop round in an emergency.

I would leave the 14 yo out of it, so she's not under any pressure, and deal with your son. If you are comfortable with him coming home alone and think he will be OK, go for it. Is there a neighbour you could make arrangements with so he knows he can go there if there are any problems, like losing his key?

My ten year old walks home, let's herself in then rings me at work. My 13 year old comes home quickly when she has no after school clubs. They both understand that they have tmdo things that they don't necessarily want to so that I can work. In the same way that I don't particularly want to drive them to football practise etc.

There is no legal age. All children are different in their ability to manage on their own, so what other people do with their children is largely irrelevant.

This leaflet from the NSPCC will give you some advice about the factors to consider when you leave your child on their own:

www.nspcc.org.uk/services-and-resources/research-and-resources/2015/home-alone-parents-leaflet/