I've just remortgaged with an offset mortgage.
I've also just got PoA for my grandmother. She has a lot of money in savings and is (or rather I am) currently selling her flat, so will soon have more than my total mortgage debt in savings.
She is in a residential home, self funding.
My question is, if I borrow money from her account, pay her back the 0.5% interest she was earning while it sat there and (for simplicity's sake) put enough money into my offset to cover the whole mortgage, then I'll effectively have a zero interest mortgage. I can pay it off much more quickly, gran doesn't lose out, win win.
This will save me a few thousand pounds every year.
Is there any tax implication to doing this? Or so long as I get it all in writing and pay her back one day can I just do what I want?