Official sources
Every rule, deadline and dollar amount on this site comes from the official publications below. We retrieved and checked each one on the date shown, and we re-check them when the agencies publish updates (for example, new Medicare premiums each fall).
Numbers in use
- Standard Part B premium 2026: $202.90 a month (CMS fact sheet, November 14, 2025).
- IRMAA tables for 2026: based on 2024 tax returns (CMS fact sheet; SSA POMS HI 01101.020; 90 FR 52063).
- IRMAA tables for 2027: not published yet. CMS usually announces next year's amounts in November; we update the moment they appear.
- Forms: CMS-40B (07/2025, OMB 0938-1230), CMS-L564 (Revised 03/2025, OMB 0938-0787), SSA-44 (12-2025, OMB 0960-0784), downloaded from cms.gov and ssa.gov.
CMS forms and fact sheets
- CMS Fact Sheet: 2026 Medicare Parts A & B Premiums and Deductibles (Nov 14, 2025) (retrieved 2026-10-24)
- CMS fact sheet: Medicare Part D 2027 National Average Monthly Bid Amount Information (Jul 28, 2026) (retrieved 2026-10-24)
- CMS-10797 Application for Medicare Part A and Part B Special Enrollment Period (Exceptional Circumstances), 07/2025 (PDF) (retrieved 2026-10-24)
- CMS-40B Request for Enrollment in Medicare Part B (Medical Insurance), form edition 07/2025 (PDF) (retrieved 2026-10-24)
- CMS-L564 Medicare Request for Employment Information, Revised 03/2025 (PDF) (retrieved 2026-10-24)
- CMS.gov forms list item: CMS 40B (retrieved 2026-10-24)
- CMS.gov forms list item: CMS L564 (retrieved 2026-10-24)
Social Security (ssa.gov)
- Form SSA-44 (12-2025) Medicare Income-Related Monthly Adjustment Amount - Life-Changing Event, OMB No. 0960-0784 (retrieved 2026-10-24)
- Social Security Act section 1839(i) (as published on ssa.gov) (retrieved 2026-10-24)
- SSA press release: Social Security Announces 3.6 Percent Benefit Increase for 2027 (2026-10-14) (retrieved 2026-10-24)
- SSA Publication No. 05-10043 'Medicare' (April 2026) (retrieved 2026-10-24)
- SSA: Forms index (SSA-44 entry) (retrieved 2026-10-24)
- SSA: Medicare Premiums: Rules for Higher-Income Beneficiaries (retrieved 2026-10-24)
- SSA: Request to lower an Income-Related Monthly Adjustment Amount (IRMAA) (page modified 09/29/2026) (retrieved 2026-10-24)
- SSA: Sign up for Medicare (retrieved 2026-10-24)
- SSA: Sign up for Part B only (retrieved 2026-10-24)
- SSA: When to sign up for Medicare (retrieved 2026-10-24)
Medicare.gov
- Medicare.gov: Avoid late enrollment penalties (retrieved 2026-10-24)
- Medicare.gov: COBRA coverage (retrieved 2026-10-24)
- Medicare.gov: Enrollment Forms (retrieved 2026-10-24)
- Medicare.gov: Medicare & the Marketplace (retrieved 2026-10-24)
- Medicare.gov: Medicare costs (2026 tables) (retrieved 2026-10-24)
- Medicare.gov: Ready to sign up for Part A & Part B (retrieved 2026-10-24)
- Medicare.gov: Retiree insurance & Medicare (retrieved 2026-10-24)
- Medicare.gov: When can I sign up for Medicare? (questionnaire results) (retrieved 2026-10-24)
- Medicare.gov: When does Medicare coverage start? (retrieved 2026-10-24)
- Medicare.gov: Who pays first (questionnaire results) (retrieved 2026-10-24)
- Medicare.gov: Working past 65 (retrieved 2026-10-24)
Social Security Program Operations Manual System (POMS)
- SSA POMS HI 00620.177 Medicare as Secondary Payer for ESRD Beneficiaries and for Employed Beneficiaries Age 65 or Over (Working Aged) (retrieved 2026-10-24)
- SSA POMS HI 00801.022 Application Requirement and Effective Date for Hospital Insurance for Insured Beneficiaries (retrieved 2026-10-24)
- SSA POMS HI 00805.075 Prescribed SMI Enrollment Forms (retrieved 2026-10-24)
- SSA POMS HI 00805.110 SMI Enrollment Processes (retrieved 2026-10-24)
- SSA POMS HI 00805.170 Conditions for Providing Equitable Relief (retrieved 2026-10-25)
- SSA POMS HI 00805.175 Evidence of Government Error or Delay (retrieved 2026-10-25)
- SSA POMS HI 00805.265 The Special Enrollment Period -- Definition - Group Health Plans (retrieved 2026-10-24)
- SSA POMS HI 00805.266 Description of Terms Used in the Special Enrollment Period and Premium Surcharge Rollback Provisions - Group Health Plans (retrieved 2026-10-24)
- SSA POMS HI 00805.270 General Eligibility Requirements for the Special Enrollment Period - Group Health Plans (retrieved 2026-10-24)
- SSA POMS HI 00805.275 Special Enrollment Period (SEP) Enrollments - Group Health Plans (retrieved 2026-10-24)
- SSA POMS HI 00805.276 SMI Effective Date for SEP Enrollments - Group Health Plans (retrieved 2026-10-24)
- SSA POMS HI 00805.277 Processing Special Enrollment Period (SEP) Enrollments (retrieved 2026-10-24)
- SSA POMS HI 00805.278 SEP Enrollments for Aged Beneficiaries with Hours' Bank Arrangements - Group Health Plans (retrieved 2026-10-24)
- SSA POMS HI 00805.280 Premium Surcharge Rollback for Individuals With GHP/LGHP Coverage (retrieved 2026-10-24)
- SSA POMS HI 00805.281 Examples of the Elimination or Rollback of Premium Surcharges for Individuals With GHP/LGHP Coverage (retrieved 2026-10-24)
- SSA POMS HI 00805.290 SEP Requirements for Self-employed Beneficiaries - Group Health Plans (retrieved 2026-10-24)
- SSA POMS HI 00805.295 Evidence of GHP or LGHP Coverage Based on Current Employment Status (retrieved 2026-10-24)
- SSA POMS HI 00805.325 GHP Coverage Under TRICARE (Formerly CHAMPUS) (retrieved 2026-10-24)
- SSA POMS HI 00805.330 Individuals with GHP Coverage Under COBRA (retrieved 2026-10-24)
- SSA POMS HI 00805.382 Special Enrollment Period (SEP) for Exceptional Conditions (retrieved 2026-10-24)
- SSA POMS HI 00805.384 Exceptional Conditions SEP for Group Health Plan (GHP) or Employer Misrepresentation (retrieved 2026-10-24)
- SSA POMS HI 00805.387 Special Enrollment Period (SEP) for Other Exceptional Conditions (retrieved 2026-10-24)
- SSA POMS HI 00805.721 Equitable Relief for Certain Individuals Dually Enrolled in Both Medicare and a Marketplace Plan (retrieved 2026-10-24)
- SSA POMS HI 00805.751 SEP and Premium Surcharge Requirements for the Aged Effective 8/86 (retrieved 2026-10-24)
- SSA POMS HI 01001.010 Premium Increase for Late Enrollment (retrieved 2026-10-24)
- SSA POMS HI 01101.010 Modified Adjusted Gross Income (MAGI) (retrieved 2026-10-24)
- SSA POMS HI 01101.020 IRMAA Sliding Scale Tables (retrieved 2026-10-24)
- SSA POMS HI 01101.030 IRMAA Determination Process (retrieved 2026-10-24)
- SSA POMS HI 01101.031 How IRMAA is Calculated and How IRMAA Affects the Total Medicare Premium (retrieved 2026-10-24)
- SSA POMS HI 01101.035 Initial IRMAA Determination Notices (retrieved 2026-10-24)
- SSA POMS HI 01120.001 Overview of New Initial Determinations on the IRMAA Using Beneficiary Provided Information (retrieved 2026-10-24)
- SSA POMS HI 01120.005 Life Changing Events (retrieved 2026-10-24)
- SSA POMS HI 01120.015 Life Changing Event (LCE) - Marriage (retrieved 2026-10-24)
- SSA POMS HI 01120.025 Life Changing Event (LCE) - Work Reduction (retrieved 2026-10-24)
- SSA POMS HI 01120.030 Life Changing Event (LCE) - Work Stoppage (retrieved 2026-10-24)
- SSA POMS HI 01120.035 Life Changing Event (LCE) - Loss of Income-Producing Property (retrieved 2026-10-24)
- SSA POMS HI 01120.040 Life Changing Event (LCE) - Reduction or Loss of Pension Income (retrieved 2026-10-24)
- SSA POMS HI 01120.043 Life Changing Event (LCE) - Employer Settlement Payment (retrieved 2026-10-24)
- SSA POMS HI 01120.055 Beneficiary Provides 2 year Old Tax Data When SSA Used 3 year Old Tax Data (retrieved 2026-10-24)
- SSA POMS HI 01120.060 Married, Filing Separately - Lived Apart All Year (retrieved 2026-10-24)
- SSA POMS HI 01120.065 Revised Estimates of MAGI (retrieved 2026-10-24)
- SSA POMS HI 01130.005 Description of the Medicare IRMAA Annual Verification Process (retrieved 2026-10-24)
- SSA POMS HI 01140.001 Overview of the Appeals Process for the IRMAA (retrieved 2026-10-24)
- SSA POMS HI 01140.005 The Reconsideration Process for the IRMAA (retrieved 2026-10-24)
Code of Federal Regulations
- 20 CFR 418.1010 (retrieved 2026-10-24)
- 20 CFR 418.1105 (retrieved 2026-10-24)
- 20 CFR 418.1115 (retrieved 2026-10-24)
- 20 CFR 418.1135 (retrieved 2026-10-24)
- 20 CFR 418.1140 (retrieved 2026-10-24)
- 20 CFR 418.1205 (retrieved 2026-10-24)
- 20 CFR 418.1210 (retrieved 2026-10-24)
- 20 CFR 418.1220 (retrieved 2026-10-24)
- 20 CFR 418.1230 (retrieved 2026-10-24)
- 20 CFR 418.1235 (retrieved 2026-10-24)
- 20 CFR 418.1255 (retrieved 2026-10-24)
- 20 CFR 418.1260 (retrieved 2026-10-24)
- 20 CFR 418.1310 (retrieved 2026-10-24)
- 20 CFR 418.1315 (retrieved 2026-10-24)
- 20 CFR 418.1330 (retrieved 2026-10-24)
- 42 CFR 406.24 Special enrollment period related to coverage under group health plans (retrieved 2026-10-24)
- 42 CFR 406.6 Application or enrollment for hospital insurance (retrieved 2026-10-24)
- 42 CFR 407.10 Eligibility to enroll (retrieved 2026-10-24)
- 42 CFR 407.11 Forms used to apply for enrollment under Medicare Part B (retrieved 2026-10-24)
- 42 CFR 407.20 Special enrollment period related to coverage under group health plans (retrieved 2026-10-24)
- 42 CFR 407.22 Request for individual enrollment (retrieved 2026-10-24)
- 42 CFR 407.23 Special enrollment periods for exceptional conditions (retrieved 2026-10-24)
- 42 CFR 407.25 Beginning of entitlement: Individual enrollment (retrieved 2026-10-24)
- 42 CFR 408.22 Increased premiums for late enrollment and for reenrollment (retrieved 2026-10-24)
- 42 CFR 408.24 Individuals who enrolled or reenrolled before April 1, 1981 or after September 30, 1981 (retrieved 2026-10-24)
- 42 CFR 411.170 General provisions (Medicare secondary payer, working aged) (retrieved 2026-10-24)
- 42 CFR 411.172 Medicare benefits secondary to group health plan benefits (retrieved 2026-10-24)
Federal Register
- Federal Register 87 FR 66454 (Nov 3, 2022), CMS-4199-F final rule implementing CAA 2021 enrollment provisions (retrieved 2026-10-24)
- Federal Register 90 FR 52063 (2025-11-19), Medicare Part B Monthly Actuarial Rates, Premium Rates, and Annual Deductible Beginning January 1, 2026 (doc 2025-20251) (retrieved 2026-10-24)