After that period, the rate reverts to the company's standard variable rate, which currently stands at 7.05 per cent.
John Willcock, N&P's head of product marketing, said: "With a market-leading rate, a free valuation and cash back or free legal fees on offer, we're confident that this is a very attractive option for anyone currently looking to buy or remortgage.
"Unfortunately with the current market changing constantly, as with other lenders, we can't guarantee how long the product will be available."
Recent research by the Fair Investment Company found that one third of borrowers would choose to get a medium term fixed rate mortgage if they were looking for a product at the moment.
It was found that 15 per cent would also choose a long-term fixed deal.
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