
Ranked by Number of CPAs
Business by LA Times Studios presents the 20 largest accounting and business advisory firms ranked by the number of CPAs in Orange County offices.
Deloitte is the largest firm in Orange County with 237 CPAs and more than 1,000 total staff in the area. Ernst & Young LLP ranked No. 2 with 180 CPAs in Orange County and PwC ranked No. 3 with 151 CPAs.
The largest local firm is independent Haskell & White LLP. The Irvine-based firm has 42 CPAs in its local office and a total local staff of 84 employees. The firm has a second office located in San Diego.
CBIZ acquired Marcum LLP, effective November 1, 2024. The numbers reported are reflectivee of post-transaction.
Overall, the 20 largest firms employ 1,422 CPAs in Orange County and have more than 4,000 total staff.
To view these lists online, visit latimes.com/b2b.
Deloitte LLP and subsidiaries 1
695 Town Center Drive, Suite 1000, Costa Mesa

deloitte.com
Ernst & Young LLP 2
18101 Von Karman Ave., Suite 1700, Irvine

ey.com
PwC LLP 3
202 Main St., Irvine

pwc.com
Moss Adams 4
2040 Main St., Suite 900, Irvine

mossadams.com
KPMG 5
20 Pacifica, Suite 700, Irvine

kpmg.com
HCVT 6
18565 Jamboree Road, Fourth Floor, Irvine

hcvt.com
RSM US LLP 7
17400 Laguna Canyon Road, Suite 200, Irvine

rsmus.com
BDO USA PC 8
600 Anton Blvd., Suite 500, Costa Mesa

bdo.com
Windes 9
2050 Main St., Suite 1300, Irvine

windes.com
CBIZ 10
2010 Main St., Irvine
600 Anton Blvd., Suite 1600, Costa Mesa

cbiz.com
Baker Tilly 11
18500 Van Karmen Ave., 10th Floor, Irvine

bakertilly.com
Haskell & White LLP 12
300 Spectrum Center Drive, Suite 300, Irvine

hwcpa.com
Armanino 13
400 Spectrum Center Drive, Suite 400, Irvine

armanino.com
RJI CPAs 14
18012 Sky Park Circle, Suite 200, Irvine

rjicpas.com
SingerLewak LLP 15
2010 Main St., Suite 300, Irvine

singerlewak.com
Withum 16
100 Spectrum Center Drive, Suite 1000, Irvine

withum.com
JLK Rosenberger 17
2601 Main St., Suite 580, Irvine

jlkrosenberger.com
CNM LLP 18
15635 Alton Parkway, Suite 450, Irvine

cnmllp.com
BPM LLP 19
300 Spectrum Center Drive, Suite 400, Irvine

bpm.com
Aldrich CPAs + Advisors 20
135 S. State College Blvd., Suite 370, Brea

aldrichadvisors.com