How the costs are calculated

The estimator and every page read the same files: five tables taken from the public CMS files of October 2026, a 2026 parameter file (deductibles, coinsurance, Medigap) and a coverage rule file written from medicare.gov. No figure is typed into a page. The CMS files were read on October 24, 2026; they cover 41 services, 109 physician fee schedule localities, 53 states and territories for medical equipment and 109 ambulance localities.

1. A doctor's approved amount

The physician fee schedule gives each service three relative value units (RVUs): physician work, practice expense and malpractice insurance. The approved amount is [(work RVU × work GPCI) + (practice expense RVU × practice expense GPCI) + (malpractice RVU × malpractice GPCI)] × conversion factor. The 2026 factor is $33.40 dollars. GPCIs are the locality's geographic indexes: picking a state and an area in the estimator changes those three indexes; with no area, the national values (1.000) apply. Practice expense has two values: the office one, higher, and the "facility" one, used when the service is done in a hospital or surgery center that bills its own rate. The same visit is worth $95 in an office and $57 when the doctor bills it in a hospital.

For imaging (MRI, diagnostic mammogram), at an imaging center the radiologist's part and the technical part are added; the technical part cannot exceed what would be paid in a hospital outpatient department, as the law requires. In a hospital, the doctor bills only the professional part and the hospital charges the rest.

2. Hospital outpatient department and surgery center

When the service is done in a hospital outpatient department, the estimator adds the hospital line with the national payment and the national unadjusted copayment of the outpatient payment system Addendum B (22 services read). One line's copayment cannot exceed the year's Part A deductible, $1,736. In an ambulatory surgery center, the center's line is the national payment of Addendum AA, and you pay 20%. These rates are national: the hospital wage index adjustment, is not modelled. That is why your real hospital's line may differ by a few dollars.

3. Your share: deductible, 20%, excess charge

The lines are taken in order. The Part B deductible you still owe ($283 at most in 2026) comes off first; then 20% applies to the rest of each line, or the hospital copayment instead. The preventive services on medicare.gov's list cost $0 and leave the deductible untouched. A screening colonoscopy that turns into polyp removal is paid at 15% with no deductible in 2026, under 42 CFR 410.152. When the doctor does not accept assignment, Medicare approves 95% of the fee and the doctor may bill up to 109.25% of the fee (the limiting charge, 15% above the reduced approved amount): for the sample visit, $14 more. The medicare.gov page on assignment explains the rule.

4. Medical equipment, ambulance, dialysis

Durable medical equipment. The DME26-D fee schedule gives a rate per state, rural and non-rural, for the 9 HCPCS codes we use. Capped rental equipment (CPAP, manual wheelchair) is paid at the full fee in months 1 to 3 and at 75% of it in months 4 to 13; after 13 months the equipment is yours (42 CFR 414.229). A power wheelchair follows the same rule with 40% in months 4 to 13. A CPAP rented for 13 months in Florida has an approved amount of $545 and leaves you $109.

Ambulance. The ambulance fee schedule gives, for each locality, an urban, rural and super rural base rate and a rate per mile; in rural areas miles 1 to 17 have a higher rate. A 25-mile basic life support emergency ride in the rest of Florida leaves you $137 with the deductible met.

Dialysis. We use the national base rate per treatment of the end-stage renal disease payment system, $281.71 in 2026, without the patient and facility adjustments CMS applies afterwards. One treatment leaves you $56.

5. Part A, Medigap and Medicare Advantage

For a hospital stay the estimator applies the Part A table per benefit period: a $1,736 deductible (days 1 to 60), $434 a day for days 61 to 90, $868 a reserve day; for a skilled nursing facility, $217 a day for days 21 to 100. With Medigap, each item is multiplied by the share the chosen letter pays according to the medicare.gov chart: 100%, 75%, 50% or nothing. With Medicare Advantage, the estimator makes up no copay: it uses the copay and coinsurance you type and limits them to what is left under your plan's yearly cap.

6. What the calculation leaves out

• The monthly Part B premium ($202.90 standard in 2026) and its income-related surcharges: they do not depend on the service.
• Anesthesia, pathology or lab fees that may come with a surgery or a colonoscopy, and drugs given during the procedure.
• Multiple procedure reductions within one session and outlier payments.
• Part D drugs, except the shingles vaccine, at $0 with a Part D plan.
• Prices of services that are not covered: for hearing aids or dental care, you type the price you were quoted.

7. Codes, licences and updates

CMS files are works of the federal government (17 U.S.C. § 105). CPT procedure codes and their descriptions belong to the American Medical Association: they are not published on this site. Each service has a name we wrote ourselves, and the link to its code is kept in a local table that is not published. Only HCPCS level II codes, maintained by CMS, are shown (for example A0429 for a basic ambulance or E0601 for a CPAP). Only part of the update is automated. A scheduled job (GitHub Actions, on the 8th of January, April, July and October, active from the site's launch) downloads the medical equipment (DMEPOS) and ambulance fee schedules again and rebuilds their tables. The physician (PFS), hospital outpatient (OPPS) and surgery center (ASC) files are updated by hand, because the link between each service and its CPT code sits in a local table that is not published: the version online is the October 2026 one, and the next manual update is planned for January 2027, with that quarter's CMS files. The yearly amounts (deductibles, premiums, Medigap) and the coverage rules are also updated by hand. The engine tests, run on every build, check known cases: deductible, hospital copayment cap, capped rental, limiting charge, Part A days.

The 2027 Part A and Part B amounts will be added when CMS publishes them, in mid-November 2026; until then they are not projected. Method version: 2026-10-24. A figure looks wrong? Write to us from the contact page.