Most ERISA disability plans require the claimant to apply for Social Security Disability as soon as they are approved for the plan benefits.  This is because the plans are usually written so that the plan gets a credit or "offset" for any amounts they may owe you under the plan for any Social Security benefits you receive.  Many plans will provide you legal assistance in helping you apply for Social Security benefits.  We at Bollwerk & Tatlow, LLC are happy to help our ERISA disability clients with their Social Security cases as well.