This stopped the individual losing out when the lifetime allowance was reduced eg fixed protection 2014 gave a lifetime allowance of £1.5m when the allowance was reduced to £1.25m. The main difference is that with fixed protection contributions must stop whereas they don’t with individual protection.

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The following HM Revenue & Customs link gives more information on fixed and individual protection:  www.gov.uk/guidance/pension-schemes-protect-your-lifetime-allowance.