I thought credit cards were best to up your credit rating. Take out a credit card and use them for everything and then pay them in full each month (so you dont pay interest). The problem with this is that it may take time to increase your credit rating.
Instead of taking a loan it would be best to use a 0% balance transfer credit card and then move this money into an ISA. As long as you pay it back before the 0% period is up (and dont use the card for cash other purchases) then you will also make some money in interest (NB: this example is simplistic and relies on other income repaying the credit card rather than using the initial amount borrowed). i.e. Assuming you borrow 3,600 on the credit card (the max for a cash isa) you will probably pay a 3% balance transfer fee so that would be 108, see below:
3600 - amount borrowed on credit card for 0%for 12 mths
108 - fee charged
216 - interest on 3600 for one year assuming 6%
you pay the credit card company 3708 and you pocket £108.
The best way to increase your credit rating would be to owe loads of money on a credit card and only pay the minimum amount per month and never miss or pay late. This however is going to cost you in interest but from the lenders point of view is hence the most profitible.
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