salary in Lonodon - decent or very good?

See what housing you can buy with that.

If you already own a house within commuting distance of London - so you only have the taxation and maintenance costs of housing - and the local schools are both OK and have places available (often mutually exclusive) then that is a decent package.

Otherwise (unless if you are childless and likely to remain so) you certainly won't have any pennies to spare.

My middle nephew and his partner both have excellent managerial level jobs but even with just one child they are unable to afford anything better than a 2-bedroom flat in a (good) suburb.

Notwithstanding the above answers about living costs, average gross earnings in London are around £40,000. So you'll be on more than twice the average wage.

But without knowing more, such as, do you have a family, what sort of lifestyle you live, if you are comfortable commuting long distances, etc. it's impossible to say if you can live comfortably on that or not.

I'd say, if you are a young single person, who's happy to live in a small one bedroom flat / studio in London, then yes, it's a good salary. On the other hand, if you have a family and want to live in a house with a garden, then no, you'll find it difficult to survive on that.

You sure you want to go now the economies fallen?