Improving Access to Advance Care Planning Act This bill provides statutory authority for Medicare coverage of advance care planning services. It also (1) allows such services to be provided by clinical social workers, and (2) waives the coinsurance and deductible for such services (regardless of whether the services are provided as part of an annual wellness visit). The Centers for Medicare & Medicaid Services must conduct outreach about Medicare coverage of advance care planning services; the Medicare Payment Advisory Commission must study and report on the provision and utilization of such services.