Whether you are able to claim from your ex-partner’s pension if you remarry very much depends on whether you fall under the new rules or the old rules. This will depend on whether you reached state pension age before 6th of April 2016. According to the current rules, you can receive a State Pension based on your husband, wife or civil partner’s National Insurance contribution at the point of claiming your own pension. However, if you remarry or enter into a new civil partnership before you make it to State Pension age you will not be entitled to receive a State Pension based on your partner’s National Insurance contribution.
The new state pension is designed to focus on your entitlements as an individual. This means that in most cases you will not be able to use an ex-partner's National Insurance record. However, divorced couples can cite their former spouse’s National Insurance contributions as a way to increase the State Pension they receive. Doing this will not affect the State Pension the other person receives.
Anyone that reached the State Pension age before the 6th of April 2016, will continue to receive the State Pension under the old system. Under the old rules, those receiving a widower’s, widow's, or civil partner’s pension will continue to get those benefits for life.
While a divorce or dissolution of a civil partnership does not invalidate any existing Wills you may have, remarrying or entering into a new civil partnership does. You may also lose an ex-partner’s pension benefits if they remove your name as their nominated beneficiary in a private pension plan.