Guides
Short answers to the questions people ask before, at, and after the lab. Every guide cites its sources. Looking for a specific test instead? Browse the test pages →
Start here
- Does Medicare cover blood work?
The one rule that decides almost every case, what "routine" costs you, why your wellness visit doesn’t include blood work, and what you pay when it is covered.
- Medicare Parts A, B, C and D explained
What each part covers and costs in 2026, why Part C is not supplemental insurance, the Medigap door that closes at 65, and where your blood work fits.
- What will your blood work cost?
Tick the tests on your order and see what Medicare pays, what you owe if covered, and what the same tests cost bought directly.
- What blood tests really cost
Every test has three prices: what Medicare pays, what you can buy it for, and what the lab bills you if Medicare says no. All 25 tests compared.
- Doctor ordered lab work? What to do before you go
Two paths: you have the order and haven’t gone yet, or you’re at the lab and they want a signature. The three choices on the ABN form, and where to buy a test directly.
- How often Medicare pays for lab tests
A free chart of screening tests and repeat tests, with who qualifies. Printable, and checked against Medicare’s own rules.
- Medicare Advantage and lab tests
The coverage rules on this site are a floor for every Medicare Advantage plan. What can differ is prior authorization, which lab you can use, and a copay. What to ask your plan before the draw.
- Normal range vs optimal range
Your lab says normal, your app says below optimal. Where each number comes from, why two major authorities disagree about vitamin D, and what it means for what Medicare pays.
Choosing your Medicare coverage
- What would each Medicare option have cost you?
Type in what you actually paid — or let the page read your medicare.gov claims file, right in your browser — and compare Original Medicare, every Medigap plan, and a Medicare Advantage plan side by side: premiums, bills, totals.
- Will a Medicare Advantage plan save you money?
Usually yes in a healthy year and up to its out-of-pocket maximum in a bad one. The letter to read before switching, the fall deadline, and the one-way door almost nobody mentions.
- Can you still get Medigap after 65?
Yes — any month of any year. The catch is health questions. Your one guaranteed window, the exceptions that reopen it, and what to do before you drop any coverage.
- Switching Medigap plans: same coverage, lower price
Every company’s Plan G is identical by law — the letter is the product, the company is just the price. How to shop it, the downgrade math, and the never-cancel-first rule.
Preparing for a test
- Fasting before blood work
How many hours, what you can still drink, what to do about your pills, and which of the common tests actually need it.
- How long does a urine culture take?
Usually 1 to 3 days, and why. How it differs from a urinalysis, how to give a clean sample, and what Medicare pays.
Understanding a test
- What is free T4?
The thyroid hormone test, how it pairs with TSH, what high and low results can mean, and what Medicare pays.
- What does a high or low ferritin level mean?
The iron-storage test, why a high number is often not about iron, and the coverage trap that gets it denied.
- What is a “basic blood panel”?
The BMP and the CMP, what each of the 8 and 14 measurements means, whether you need to fast, and what Medicare pays.
- What is BUN on a blood test?
The kidney number on your metabolic panel, why it moves for reasons that have nothing to do with kidneys, and what the BUN/creatinine ratio is for.
- What is hs-CRP?
The high-sensitivity inflammation test used for heart risk, how it differs from a standard CRP, and why Medicare almost never covers it.
- What does a high B12 level mean?
The most common cause is the plainest one. What else can raise it, what low B12 points to, and the vitamin-panel coverage trap.
- What does a folate test show?
What causes low folate, what a high result usually means, what the test is not used for, and why it can be the one uncovered line on your draw.
Screenings Medicare covers
- Does Medicare cover a bone density test?
The five conditions that qualify, once every 24 months or more often when medically necessary, $0 if the provider accepts assignment, and the gap between Medicare’s rule and the age-65 screening advice.
- Does Medicare cover mammograms?
Baseline, screening, and diagnostic mammograms: who qualifies, once every 12 months, $0 for screening, 20 percent for diagnostic, and the "11 full months" rule.
- Does Medicare cover a colonoscopy?
Every 10 years at average risk, every 2 years at high risk, no upper age in the rule as written, $0 for screening, and exactly what you pay in 2026 if a polyp is removed.
- Does Medicare cover Cologuard (the stool DNA test)?
Ages 45 to 85 at average risk, once every 3 years, $0 with assignment, the follow-up colonoscopy after a positive result also at $0, and the rule change that takes effect in January 2027.
- Does Medicare cover a blood test for colon cancer?
Ages 45 to 85 at average risk, once every 3 years, $0 with assignment, and why medicare.gov still says "if available."
- Does Medicare cover a hepatitis B test?
Who counts as high risk in Medicare’s own words, one screening or yearly, during pregnancy, $0 with assignment, and the case that is not covered.
- Does Medicare cover STI screening?
Chlamydia, gonorrhea, syphilis, and hepatitis B screening once a year, who counts as increased risk, the two counseling sessions, and $0 with assignment.
- Does Medicare cover Pap smears?
Once every 24 months, or every 12 months at high risk, the pelvic exam that goes with it, $0 with assignment, and what Medicare’s rule says about age.
- Does Medicare cover an HPV test?
Once every 5 years, ages 30 to 65, only together with a Pap test, $0 with assignment.
When Medicare says no
- How to appeal a Medicare denial
First, whether you owe anything. Then the Medicare Summary Notice, the 120-day deadline, the form or a letter, the five levels with the 2026 dollar minimums, and how Medicare Advantage differs.
- How to appeal a hospital discharge (the fast appeal)
A different, faster process: the Important Message from Medicare, the deadline in its own words, who to call in your state, and what happens to the charges while the appeal is pending.
- What Medicare means by "reasonable and necessary"
The sentence in the law, CMS’s three tests, what an NCD and an LCD are, and why the 23 lab rules come with diagnosis lists that let this site give a straight answer.
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