Timothy Mountcastle, MD
Timothy Mountcastle, MD is a Surgery Physician in Ashburn, VA, registered under NPI 1821015561. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 44095 PIPELINE PLAZA, SUITE 430, Ashburn, VA 20147. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 0101239935 | VA | Surgery Physician primary |
| 0101239935 | VA | Plastic Surgery Physician |
This provider holds licence 0101239935 issued in VA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Plastic And Reconstructive Surgery
- PAC ID
- 8820066293
Enrolled in Medicare 2 times, across 2 states:
| State | Enrollment ID | Provider type |
|---|---|---|
| Virginia | I20061110000291 | Practitioner - Plastic And Reconstructive Surgery |
| District of Columbia | I20080616000314 | Practitioner - Plastic And Reconstructive Surgery |
Medicare enrolment is recorded as approved under the provider type Practitioner - Plastic And Reconstructive Surgery. There are 2 separate enrolment records across 2 states (VA, DC). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Surgery covers
A general surgeon has expertise related to the diagnosis - preoperative, operative and postoperative management - and management of complications of surgical conditions in the following areas: alimentary tract; abdomen; breast, skin and soft tissue; endocrine system; head and neck surgery; pediatric surgery; surgical critical care; surgical oncology; trauma and burns; and vascular surgery. General surgeons increasingly provide care through the use of minimally invasive and endoscopic techniques. Many general surgeons also possess expertise in transplantation surgery, plastic surgery and cardiothoracic surgery. NUCC Health Care Provider Taxonomy, code 208600000X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 208600000X | Surgery Physician | 0101239935 | VA | primary |
| 208200000X | Plastic Surgery Physician | 0101239935 | VA |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1821015561 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 17, 2006 |
| Last updated | Dec 13, 2023 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
44095 PIPELINE PLAZA, SUITE 430 Ashburn, VA 20147 (703) 858-3208 Fax (571) 291-2289 |
| Mailing address |
224-D CORNWALL STREET, NW, SUITE 403 Leesburg, VA 20176 |
| Other identifiers |
1821015561
· Medicaid (VA) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 8 | 2 | 1 | 0 | 1 | 5 | 5 | 6 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 4 | 1 | 0 | 1 | 1 | 5 | 3 |
Sum = 49 · next multiple of 10 = 50 · check digit = 1 · actual last digit = 1
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.