Despite its long term, the conditions of the mortgage allow borrowers to opt out of the product after a decade without having to pay any charges.
Matthew Carter, mortgages director at Nationwide, added that the mortgage offers people long term stability to protect them against "fluctations in interest rates".
He added: "We also recognise that people who want a mortgage for life don't necessarily want a house for life which is why the mortgage is fully portable, allowing borrowers to take it with them as they move up the property ladder."
Recent research by Abbey claimed that fixed rate mortgages are growing in popularity in the UK.
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