I might look at it rather as Op did.
Firstly, I’d say that with £6k rent, the max amount of around £10k will probably be sufficient. He doesn’t need £10k plus £300 per month, regardless of the source.
Where the £10k comes from depends on how much you can afford to support him. He might be ENTITLED to the full loan but if he doesn’t need to take the max debt because you are able to give him some each month, then he can take a smaller loan and have less debt in future. Yes, I know it won’t alter early payments BUT it will reduce how long the loan is being paid off for/when it is cleared and amount of compound interest.
Im always surprised that when parents can afford to partly support their kid, they do and STILL encourage them to take the max loan available, without ever looking into if a smaller loan might be sufficient. Lots have bigger debt than needed.
Re the £20k I think it’s a different issue. I’d see that money as for the future not for funding supermarket shopping or beers. He doesn’t need it to live on anyway as rent is low and he will have sufficient outside of it. You say he’s a sensible lad….well if you run through the finances of what he will have anyway, esp if he gets a summer holiday job, hopefully he’ll see he isn’t going to be hard up anyways
Best advice would be for the money to be put into a different account and the details are left behind at home. No way should it be sitting in his current account…but hopefully it’s somewhere earning decent interest and ideally locked away even in one year accounts rather than easy access. And I agree that it’s best to just not mention to anyone that the money exists.
If he really doesn’t want to lock it all away, can you reach an agreement that he will take an additional £2k per year but leave the rest locked away? As a bright boy, he will be able to grasp that having all of it accessible could mean whizzing through it very fast, with no real gain and a sense of regret later.
Sounds like you need to do some budgeting with him . Rent plus all the other expenses, including going out. Consider more what you might give him and what loan he might take and what total amount he’ll have. As long as he has enough he probably will be happy to leave the £20k behind. I suspect he’s worried about missing out or being poor at uni and sees the £20k as a way to avoid that. But there doesn’t seem to be any reason why
he would be hard up anyway. It’s just that he doesn’t know that.
Where is the money at the moment? Surely it’s not just in his current account.
At the end of the day it is his though. Most would be able to see it’s a good sum for the future if they really think about it. But having it in the current account would make it do easy to waste, even without planning to.