Is Januvia (sitagliptin phosphate) covered by Medicare Part D?
5,052 of 5,052 Medicare Part D plan offerings (100%) list Januvia on their 2026 formulary, most often on tier 3; 0.3% of the formularies that cover it require prior authorization. Part D spending on it was $3.8 billion in 2024 for 828,288 people: what plans and patients paid at the pharmacy, before manufacturer rebates (CMS Part D Spending by Drug).
- Plans that cover it
- 100%
- 5,052 of 5,052 offerings; the median drug: 76%
- Usual tier
- Tier 3
- from tier 1 to tier 6
- Prior authorization
- 0.3%
- of formularies that cover it; the median drug: 1%
- Quantity limits
- 98.2%
- of formularies that cover it; the median drug: 30%
Source: CMS Part D formulary file, 2026 second quarter: the formularies in use in 2026. A plan's 2027 formulary can differ; check your own plan's coverage in Medicare Plan Finder.
What does it cost under Part D in 2027?
- A negotiated price
- Medicare negotiated a lower price for Januvia, in effect from January 1, 2026: $113 for a 30-day supply, against a list price of $527 (2023). Where your share is a percentage of the drug's price, it is a percentage of the lower price; a flat copay stays as your plan sets it.
- Your yearly cap in 2027
- Out-of-pocket spending on covered Part D drugs stops at $2,400 in 2027 ($2,100 in 2026); after that, you pay nothing for covered drugs for the rest of the year.
- The deductible
- A plan's drug deductible is at most $700 in 2027 ($615 in 2026); many plans charge less or none.
Source: CMS, Announcement of calendar year 2027 Part D parameters; Medicare.gov, “How much does Medicare drug coverage cost?”; CMS, “Selected drugs and negotiated prices” (read Oct. 7, 2026).
How much does Medicare spend on it?
Part D spending by year
828,288 people filled it under Part D in 2024, in 4,027,317 claims. The amounts are what plans and patients paid at the pharmacy, before manufacturer rebates.
Source: CMS Medicare Part D Spending by Drug, 2020 to 2024 (published June 2026). Row used: Januvia (Sitagliptin Phosphate).
Which forms and strengths are counted?
- sitagliptin phosphate 100 mg oral tablet
- sitagliptin phosphate 25 mg oral tablet
- sitagliptin phosphate 50 mg oral tablet
What else should you check?
- Stand-alone drug plans for 2027Premiums and deductibles
- Drugs Medicare spends the most onThe 2024 spending list
- 2027 costs and limitsDeductibles and out-of-pocket limits
Data, not medical advice. Coverage is the share of plan formularies listing the drug; your plan's formulary, tier and pharmacy decide what you pay.