The Offset Mortgage

What is an offset mortgage? It’s more flexible than a conventional mortgage and could also help to pay off your debt more quickly.

How it works is that you set up a savings account with your mortgage lender and the savings account is linked to your mortgage account. As a result, your savings don't earn interest; but are used to reduce the mortgage balance.

This is attractive for three reasons:

1. Mortgage interest rates tend to be higher than savings rates, so your savings are generating a higher return for you.

2. You have flexibility. Your savings can be used to reduce your mortgage for a while but can be switched if they're needed somewhere else.

3. Offset mortgages offer tempting tax advantages.

So if you had a £100,000 mortgage with £10,000 in the savings account, you would accrue interest only on the £90,000 portion. And you won't pay any tax on the reduced mortgage interest that you pay.

Here is an example: £10,000 in an account paying 5% AER would earn £500 in gross interest over a year - £400 for a lower rate taxpayer and £300 for a higher rate. Over 10 years a lower rate taxpayer would make £4802 and a higher rate £3,439.
At the same time, a £100,000, 10-year mortgage at 6% would accrue £33,224 in interest. By using that £10,000 to offset the loan (and effectively make it £90,000) you would accrue £19,902 in interest, £13,322 less.