Top 100 Contractors in NAICS 621: Ambulatory Health Care Services, Aug 2025–Jul 2026
Parent companies by net contract obligations Aug 1, 2025 – Jul 31, 2026 Code page on GovTribe
The latest 12 months. See the newest fiscal year's list: Top Contractors in NAICS 621: Ambulatory Health Care Services, FY2025.
The top 10 won 77% of NAICS 621 contract dollars from August 2025 through July 2026
Ranking facts
- Contract obligations
- $15,316,683,090 Net of deobligations, by contracts coded NAICS 621 or a code under it
- Contractors
- 2,009 Parent companies with an obligation
- Largest contractor
- Leidos Holdings, Inc. $3.73 billion, 23.2% of obligations
- Data as of
Contract actions from FPDS (SAM.gov). How the rankings work · Download all 100 rows as CSV · Free to reuse with credit to GovTribe (CC BY 4.0)
Full ranking
| Rank | Contractor | Net obligations | Share | Trend |
|---|---|---|---|---|
| 1 | $3,729,362,712 | |||
| 2 | $2,997,785,820 | |||
| 3 | $2,634,071,417 | |||
| 4 | $2,052,783,256 | |||
| 5 |
Fresenius Medical Care Holdings Inc.
|
$353,874,488 | ||
| 6 | $235,058,813 | |||
| 7 | $160,673,170 | |||
| 8 |
Amergis Healthcare Staffing Inc.
Top agencies
|
$79,999,744 | ||
| 9 | $79,226,533 | |||
| 10 | $77,145,920 | |||
| 11 | $72,610,900 | |||
| 12 |
Laboratory Corporation of America Holdings
|
$71,795,234 | ||
| 13 | $71,607,531 | |||
| 14 |
Acuity International LLC
|
$66,726,121 | ||
| 15 | $64,814,546 | |||
| 16 | $59,243,408 | |||
| 17 | $54,389,602 | |||
| 18 | $52,606,142 | |||
| 19 |
KBR Wyle Services LLC
|
$47,457,545 | ||
| 20 | $45,585,293 | |||
| 21 |
Vetmed Group LLC
|
$39,894,972 | ||
| 22 |
US Renal Care Inc.
Top agencies
|
$39,287,141 | ||
| 23 | $38,092,389 | |||
| 24 | $37,693,796 | |||
| 25 | $35,943,011 | |||
| 26 | $33,880,344 | |||
| 27 |
Luke & Associates Inc.
Top agencies
|
$32,258,646 | ||
| 28 | $31,832,729 | |||
| 29 |
Aims-Usgp JV LLC
Top agencies
|
$31,792,024 | ||
| 30 | $30,488,058 | |||
| 31 | $29,941,850 | |||
| 32 | $29,873,993 | |||
| 33 |
Roche Holdings Inc.
Top agencies
|
$29,769,660 | ||
| 34 |
Giacare & Medtrust JV LLC
Top agencies
|
$27,406,706 | ||
| 35 | $27,125,903 | |||
| 36 | $24,820,373 | |||
| 37 | $22,820,292 | |||
| 38 | $22,346,675 | |||
| 39 |
Aspire-Luke JV LLC
Top agencies
|
$21,000,795 | ||
| 40 | $20,869,402 | |||
| 41 | $20,291,237 | |||
| 42 |
Center for Disease Detection, LLC
|
$19,945,626 | ||
| 43 | $19,717,755 | |||
| 44 | $19,617,368 | |||
| 45 |
Matrix Providers Inc.
Top agencies
|
$19,139,653 | ||
| 46 | $19,064,887 | |||
| 47 | $18,238,286 | |||
| 48 | $18,063,386 | |||
| 49 | $17,239,756 | |||
| 50 | $17,027,173 | |||
| 51 |
Accenture Federal Services LLC
Top agencies
|
$16,515,595 | ||
| 52 |
BMC Software Inc.
|
$15,613,356 | ||
| 53 | $15,056,124 | |||
| 54 | $14,954,638 | |||
| 55 |
Medtronic Inc.
Top agencies
|
$14,703,257 | ||
| 56 | $14,432,858 | |||
| 57 | $14,330,109 | |||
| 58 | $14,152,466 | |||
| 59 | $13,752,656 | |||
| 60 |
Oneerp Solutions LLC
|
$13,539,886 | ||
| 61 | $13,252,613 | |||
| 62 | $13,023,256 | |||
| 63 |
Transox Inc.
Top agencies
|
$12,776,728 | ||
| 64 | $12,582,966 | |||
| 65 | $12,534,061 | |||
| 66 | $12,448,373 | |||
| 67 | $11,985,877 | |||
| 68 |
PDQ Health Services, LLC
Top agencies
|
$11,686,138 | ||
| 69 | $11,598,661 | |||
| 70 |
CG Services LLC
Top agencies
|
$11,379,006 | ||
| 71 | $11,353,978 | |||
| 72 | $11,051,997 | |||
| 73 | $10,995,832 | |||
| 74 | $10,988,538 | |||
| 75 | $10,919,074 | |||
| 76 | $10,600,965 | |||
| 77 | $10,416,548 | |||
| 78 |
Boosted Commerce Inc.
Top agencies
|
$10,191,784 | ||
| 79 |
Crassociates, Inc.
Top agencies
|
$9,945,210 | ||
| 80 | $9,781,999 | |||
| 81 | $9,718,878 | |||
| 82 | $9,671,705 | |||
| 83 | $9,629,067 | |||
| 84 | $9,407,797 | |||
| 85 |
Forensic Drug & Alcohol Testing LLC
|
$9,381,775 | ||
| 86 | $9,317,687 | |||
| 87 | $9,201,565 | |||
| 88 | $8,753,182 | |||
| 89 |
Sonora Quest Laboratories LLC
|
$8,690,361 | ||
| 90 | $8,621,159 | |||
| 91 |
Aleknagik Technology, LLC
Top agencies
|
$8,230,704 | ||
| 92 | $8,101,151 | |||
| 93 | $7,986,113 | |||
| 94 |
Tryfacta Inc.
Top agencies
|
$7,904,922 | ||
| 95 | $7,665,205 | |||
| 96 | $7,599,896 | |||
| 97 | $7,454,439 | |||
| 98 | $7,314,135 | |||
| 99 | $6,919,961 | |||
| 100 |
Allosource
Top agencies
|
$6,881,184 |
Show 75 more
100 of 2,009 contractors listed here. See the rest on GovTribe.
Rankings for the codes under NAICS 621
| Code | Net obligations | Largest contractor |
|---|---|---|
| 6211 Offices of Physicians | $12,156,135,264 | Leidos Holdings, Inc. |
| 6214 Outpatient Care Centers | $1,328,661,665 | Fresenius Medical Care Holdings Inc. |
| 6219 Other Ambulatory Health Care Services | $1,031,008,965 | Amergis Healthcare Staffing Inc. |
| 6215 Medical and Diagnostic Laboratories | $409,127,870 | Laboratory Corporation of America Holdings |
| 6213 Offices of Other Health Practitioners | $329,381,319 | Kbr, Inc. |
| 6216 Home Health Care Services | $39,525,446 | Warrior Service Company LLC |
| 6212 Offices of Dentists | $22,842,561 | Sterling Medical Associates, Inc. |
How this ranking works
- Source: every contract action FPDS records (as published on SAM.gov) in the period, as GovTribe received it.
- Amounts are net obligations: what was obligated, less what was deobligated. Shares are of $16.1 billion obligated before deobligations, so they never pass 100%.
- Parent companies: each action counts under the ultimate parent its award record names, or under the awardee when it names none, so no dollar counts twice. An awardee whose own actions mostly name no parent, and that no other company's actions name as their parent, rolls up its SAM.gov registration's chain of parent companies: it counts under the first company there that other companies' actions name as their parent, or under the parent most of a company's own actions name, whichever comes first; with neither, under the highest company in the chain with federal contracts of its own. Joint ventures stay companies of their own. Parents of the same name (Inc., LLC and the like aside) count as one company, since FPDS records a company's parent under more than one UEI over time. GovTribe corrects a few parents and names by hand; see the corrections.
- Period: the trailing 12 months end with the last month that ended at least 90 days ago, because the Department of Defense reports its contract actions to FPDS about 90 days late. The list is rebuilt each night.
- Rank changes compare with Aug 2024–Jul 2025. "New" marks a company outside that period's top 500, and "Returned" one of those that was on an earlier fiscal year's list.
- Rank lines show each company's rank on every fiscal year's list since FY2021, #1 at the top, on a scale that gives the top of the list more room. A dashed stretch spans years it wasn't on the list.
- Placeholder recipients FPDS uses when it names no company ("Miscellaneous Foreign Contractors" and the like) aren't ranked.
Quick answers
Who were the top 10 NAICS 621 contractors in Aug 2025–Jul 2026?
1. Leidos Holdings, Inc. ($3.73B), 2. UnitedHealth Group Incorporated ($3B), 3. Maximus Federal Services, Inc. ($2.63B), 4. Loyal Source Government Services LLC ($2.05B), 5. Fresenius Medical Care Holdings Inc. ($354M), 6. Davita Inc. ($235M), 7. Valor Healthcare Inc. ($161M), 8. Amergis Healthcare Staffing Inc. ($80M), 9. Decypher Technologies Ltd ($79.2M), 10. Kbr, Inc. ($77.1M).
On GovTribe
Research every contractor on this list
- Every contract, task order and IDV they hold
- Their subsidiaries, teammates and competitors
- Open opportunities they're positioned for
- Alerts when they win new work