Michael L Chaffin, NP
Nurse Practitioner · Mountain View
- Medicare standing
- Clear
- Enrolled, allowed to bill and order, not excluded
- Plans that list them
- 1
- 1 carrier
- Offices
- 6
Offices
6 locations · Sutter Bay Medical Foundation · 3,783 clinicians in this group
Plans that list them
1 plan · 1 carrier
A missing listing does not mean out of network. Directories change, and a listing does not cover every office. Call Michael L Chaffin’s office to confirm they take your plan. Ask about the office you use, its medical group, referrals and appointments.
| Alignment Health Sutter Advantage +More (HMO) | Alignment Health Plan | Listed | Oct 3, 2026 |
California Medical Board record
Licence A20962 · Cancelled
Licence status: Cancelled · since 1963 · University of Manitoba Faculty of Medicine.
License has been voluntarily canceled, or the license has been expired for at least five years and has not been renewed. No practice is permitted.
Matched on the licence number without its letter prefix; check the name before relying on it.
No disciplinary actions, convictions, malpractice judgments or citations in this record.
Original Medicare doctor bills
$3,392
Medicare paid this office $3,392 for 139 people.
This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.
| Anticoagulant management of patient taking warfarin | 131 | $1,734 | $9 |
Who their Medicare patients are
139 Original Medicare patients in 2024. Average age 77 · Women 45% · Also on Medicaid 19% · Health risk score 1.74. Above the middle of the specialty; the typical nurse practitioner clinician is at 1.42.
Conditions among them: High blood pressure 75% · Atrial fibrillation 69% · Heart failure 45% · Chronic kidney disease 45% · Diabetes 40% · Coronary heart disease 36% · COPD 19% · Depression 15% · Cancer 14% · Stroke 12% · Dementia 9%.
The office billed $15,855, Medicare allowed $4,287 and paid $3,392; for 209 services of 6 kinds.
Original Medicare patients only. A risk score of 1.0 is the average Medicare patient; higher means sicker. Any count under 11 is hidden.
Year by year
| 2024 | 139 | 209 | 77 | 1.74 | $15,855 | $3,392 |
| 2023 | 57 | 100 | 69 | 3.28 | $31,972 | $7,421 |
| 2022 | 24 | 35 | 72 | 2.85 | $9,450 | $2,061 |
Original Medicare only. A service billed for fewer than 11 people in a year is hidden, so the lines can add up to less than the year's total.
See the services billed each year
2023: 2 services
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 36 | $3,398 | $60 |
| Subsequent hospital care with moderate levelof medical decision making at least 50 minutes | 15 | $2,779 | $90 |
2022: 1 service
| Subsequent hospital care with moderate levelof medical decision making at least 35 minutes | 20 | $1,498 | $53 |
Drugs they prescribed that Part D paid
$4,648
Pharmacies billed $4,648 in 2024.
This is pharmacy cost, not the office bill, and not what patients paid.
Opioids were 0% of their Part D prescriptions (0 of 107) in 2024. At or below the middle of the specialty; the typical nurse practitioner clinician is at 0%.
107 generic and 0 brand-name prescriptions · $4,648 in drug cost.
Part D prescriptions only. The opioid rate is opioid prescriptions as a share of all this clinician's Part D prescriptions; surgeons and pain specialists run higher than others, so it is shown against the same specialty.
| Enoxaparin | 26 | $3,682 | $142 |
| Warfarin | 47 | $524 | $11 |
| Clopidogrel | 13 | $217 | $17 |
Year by year
| 2024 | 107 | 64 | 0% (0) | 0% | $4,648 |
| 2023 | 41 | 16 | 0% (0) | None | $2,588 |
| 2022 | 27 | 13 | 0% (0) | None | $764 |
| 2021 | 13 | None | 0% (0) | None | $188 |
| 2020 | 12 | None | 0% (0) | 0% | $213 |
| 2019 | 14 | None | 0% (0) | 0% | $240 |
| 2018 | 19 | None | 0% (0) | None | $289 |
| 2016 | 17 | None | None | None | $512 |
| 2015 | 24 | None | None | None | $1,304 |
| 2014 | 53 | 17 | 23% (12) | None | $2,384 |
| 2013 | 52 | 14 | 25% (13) | None | $1,439 |
Part D prescriptions only. A drug prescribed to fewer than 11 people in a year is hidden.
See the drugs prescribed each year
2014: 1 drug
| Tramadol | 12 | $68 | $6 |
2013: 1 drug
| Tramadol | 11 | $63 | $6 |
Money from drug and device companies
$87 in 2025
| 2025 | 1 | 2 | None | $87 |
| 2024 | 1 | 1 | None | $36 |
| 2023 | 2 | 5 | None | $335 |
| 2022 | 1 | 6 | None | $120 |
| 2021 | 1 | 1 | None | $25 |
Paid work is consulting, speaking, honoraria and royalties, as opposed to meals and travel.
A payment is not proof that care is biased.
| Boston Scientific | Angiojet Xmi | $87 | 2 payments
|
See all 2 published payments
| Boston Scientific | Meals · 2025-11-11 | Angiojet Xmi | $53 |
| Boston Scientific | Meals · 2025-02-13 | Jetstream Sc | $34 |
See earlier years (2024, 2023, 2022, 2021)
2024: $36
| Boston Scientific | Ranger | $36 | 1 payment
|
2023: $335
| Boston Scientific | Jetstream Sc | $217 | 4 payments
|
| Abiomed | Impella | $119 | 1 payment
|
2022: $120
| Boston Scientific | Jetstream Sc | $120 | 6 payments
|
2021: $25
| Abbott Laboratories | Heartmate 3 Left Ventricular Assist Device | $25 | 1 payment
|
Checkups this office reported
Medicare did not publish checkup rates for this clinician.
- Medicare’s overall office score
- 82.4 / 100
- Scores the office’s reporting and systems. It is not a grade for how the doctor treats you.
Professional record
- NPI
- 1558640235
- Licence
- CA 20962California A20962: Cancelled
- Video visits
- Lists video visits
- Gender
- Male
More record details
- Sole proprietor
- No
- Taxonomy
- Nurse practitioner (363L00000X)
- Mailing address
- 325 Distel Cir, Los Altos, CA, 94022
- NPI first listed
- 2011-08-11
- NPI last updated
- 2024-04-03
- NPI record certified
- 2024-04-03
This is when the NPI record was last certified, not a medical board exam.
Extra NPI addresses: 2540 East St, Concord, CA, 94520
This office lists an electronic records connection.