Redundancy payment coming in April - how can I minimise the savings tax bill?

Cycler

I have taken voluntary redundancy, finishing at the end of March. I've got a £65k net redundancy payment coming on 22nd April 2025. I will also get around £32k of maturing shares around September. 

I've got £16k ISA allowance remaining for 24/25 and my wife has her full allowance for 24/25 too. However, I don't have any available cash to use up the allowance before the redundancy payment.

I would like to find a way to use up this year's ISA allowances so we can use next year's allowances for as much of the remainder as possible.

My current thinking is to take out a loan in early March for £36k to fill up the ISA and then pay off the loan in April with the redundancy money. Is that possible? Do you know of the best loans to do that? Will the interest cost be cheaper than the tax on savings interest if I just held the cash in a savings account?

Would approaching my mortgage provider be an option? I expect I would not be able to pay the full £36k back in one go as it is over the 10% repayment cap on the full remaining mortgage.

I've also thought about borrowing off relatives/friends but I don't know of anyone who would have that amount available.

I appreciate this is very "first-world problems" and I am very grateful to be in this position.

Cycler

Just to add, I'm also considering putting it in my pension but my focus is on bolstering my savings that are accessible before I reach 57 as the pension is pretty well catered for at the moment. I am 46 now and considering finishing work in my early 50s

JGB1955

I think you may be over-thinking this.  In April put £20K into ISAs for both you and your wife.  The remaining £25k /£57K, split between the two of you, is going to (optimistically) earn £2,300 - all of which, apart from £300 will be covered by your Personal Savings Allowance.  So---on a bad day, £30 each tax to pay.  Is it really worth all those hoops  you're trying to jump through?

born_again

Do you have a new job lined up?
Are you certain that you will find a new job quickly, as a delay will mean that some of your pay out will be used to replace your previous income, thus bringing down any protentional tax on interest.

65K would give you both 20K in a isa & as above the protentional tax is going to be very low on the remainder. 
Could even treat yourself to something you need or a holiday to cut it down even further.

Life is to short & being able to enjoy something like this is worth it.

Cycler

Thanks both for putting it in perspective.

I am thinking of taking a break for a few months so, yes, that should also reduce it down.

Thanks again!