If you are on both Medicare and full Medicaid and your income sits at or below the federal poverty line, your copay for generic drugs is set to drop to $0. Not today, and not next year. The change starts with plan years beginning January 1, 2028, according to the proposed rule the Centers for Medicare & Medicaid Services published in the Federal Register on Tuesday, October 20, 2026.
Is this already decided?
The $0 copay is. The rule is not. Congress wrote the change into section 6219 of the Consolidated Appropriations Act, 2026, which became law on February 3, 2026. That section cuts the generic copay "from $1 to $0" for this group, effective for plan years on or after January 1, 2028. The $1 is the statute's base figure, adjusted each year for inflation. CMS says that for plan year 2026 the amount is $1.60 for generics and $4.90 for other covered Part D drugs.
What CMS released Tuesday is the paperwork that writes the law into Medicare's regulations. CMS calls the copay section "narrowly tailored" and says it "does not introduce any discretionary policy changes." Read plainly, the agency is not choosing whether this happens. Congress already did. The proposal stage matters more for the rule's other pieces, including new limits on pharmacy benefit managers and Medicare Advantage provider directory requirements.
Who qualifies
The rule covers "full-benefit dual eligible" people, meaning those enrolled in Medicare and full Medicaid, with incomes that do not exceed 100 percent of the federal poverty level. CMS estimates about 6 million enrollees would be affected, based on 2026 enrollment data.
Two limits matter. The change applies to generic drugs only, so the copay on other covered drugs is untouched by this section. And dual eligibles with incomes above the poverty line keep their current copay structure under the existing rules CMS describes.
Does anything change today?
No. Your copay at the pharmacy counter tomorrow is the same as it was yesterday. Publication opens a public comment period. Under the Federal Register's official record for the document, comments close December 15, 2026, and no effective date has been set because the rule is still a proposal. CMS will have to issue a final rule before the regulation text takes effect.
What to do with this
If you help a parent or neighbor who fits this description, nothing needs to happen now. The time to check is when 2028 plan information comes out. CMS says marketing and communications rules in this proposal would apply to contract year 2028 materials beginning October 1, 2027, which is when plans start selling 2028 coverage.
Anyone can comment on the proposal at regulations.gov under file code CMS-4214-P until December 15.
The law already says zero. The rule just has to catch up by 2028.