Affordable Insulin Now Act This bill limits cost-sharing for insulin under private health insurance and the Medicare prescription drug benefit. Specifically, the bill caps cost-sharing under private health insurance for a month's supply of selected insulin products at $35 or 25% of a plan's negotiated price (after any price concessions), whichever is less, beginning in 2023. The bill caps cost-sharing under the Medicare prescription drug benefit for a month's supply of covered insulin products at (1) $35 between October 1, 2022, and January 1, 2024; and (2) $35 or 25% of a plan's negotiated price, whichever is less, beginning in 2024. The bill provides funds for FY2022 for the Centers for Medicare & Medicaid Services (CMS) to implement the bill. Currently, the CMS is testing a voluntary model under the Medicare prescription drug benefit (the Part D Senior Savings Model) in which the copayment for a month's supply of insulin is capped at $35 through participating plans. The model is set to expire on December 31, 2025.