Discussing the new offer, which is expected to run from now until the end of next year, chief executive of M&S's money division Brendan Cook said the discounts were "great value".
He explained: "M&S life insurance already represents great value for our customers with both level and decreasing term cover available from £5 per month, so we are pleased to be able to pass on an additional five per cent saving to customers who choose to apply online."
M&S launched its financial services division in 1985, but rebranded the company in October 2003.
The company was recently named Best Life Insurance Provider 2007 at the Your Money awards and was commended by Moneyfacts for its competitive term assurance.
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