About Part B Forms

Last updated November 12, 2026

Part B Forms explains the Medicare paperwork that trips people up when they retire after 65: signing up for Part B late with Forms CMS-40B and CMS-L564, and lowering an IRMAA surcharge with Form SSA-44.

The official instructions are written for the agencies, not for you. The top search results are often PDF-filler sites and forum threads. We write the guide we'd want for our own parents: plain English, filled-in examples, large text, and sources you can check.

How we make money

The guides and calculators are free. We sell two optional PDF kits with complete filled examples, evidence checklists and cover letters. We don't sell insurance, take commissions from plans, or show ads from Medicare plan sellers.

How we check facts

Every figure comes from cms.gov, ssa.gov, medicare.gov or Social Security's operations manual (POMS). Each page shows when it was last checked and links to its sources. Read our editorial policy.

Not affiliated

Part B Forms is an independent guide operated by Atomic Development (Serbia). It is not affiliated with or endorsed by Medicare, the Centers for Medicare & Medicaid Services (CMS), or the Social Security Administration (SSA). The official forms are free from cms.gov and ssa.gov. Nothing here is legal or financial advice.

Questions or corrections: contact us.