Accepted Certified Plumbing Companies Providing Backflow Related Services

The average cost is between $100-$180 per backflow assembly test (this is an average some companies may charge more).

  • If you do not see a plumbing company on our list, please have them contact us by email or phone before you schedule with them. We need to verify that they are licensed and certified in accordance with Maryland regulations to perform cross-connection/backflow prevention-related plumbing services in AACO. If a Company is not on our list and we have not verified their information the AACO Backflow Program reserves the right to not accept a test report performed by said Company.

  • All companies performing backflow tests are required to turn in paperwork to us within 30 days of the test date.

  • If a company from our list performs a backflow test and does not turn in the required paperwork to us they will be suspended from our list for 90 days.

  • After three suspensions, the company will be permanently removed from our list.

Disclaimer

This consolidated list of plumbing companies was compiled by the AACO Backflow Program as a convenience for our customers. AACO Backflow Program has verified that the plumbing companies on this list are licensed and certified following Maryland regulations to perform cross-connection/backflow prevention-related plumbing services. Inclusion on this list is entirely voluntary. The companies listed do not work for nor are they associated in any way with AACO Backflow Program and AACO Backflow Program assumes no liability for any work performed by a listed company.

AACO Backflow Program does not endorse or recommend any company on this list, nor do we set the pricing for these companies. We suggest customers obtain multiple estimates before hiring a plumbing company to test their backflow preventer.

 

Company NamePhone Number
Anne Arundel Plumbing410-437-0300
Old Line Plumbing410-553-0134
Trust Plumbing & Heating LLC443-269-8929
Durance Plumbing301-270-6663
Long Point Plumbing443-623-5667
Calvert Plumbing & Backflow443-995-4228
B&C Plumbing301-440-4687
Dwyer Plumbing410-647-3030
Mahon Plumbing Inc.410-636-7944
AM Bell Plumbing301-750-2258
Fireline Corporation410-247-1422
Anytime Plumbing & Drain301-300-9883
Howard Plumbing LLC410-353-6215
Alpha Plumbing Inc.410-255-5998
Heidler Plumbing410-268-7191
Mike Jones Plumbing LLC202-368-1463
N&E Plumbing703-365-7173
MPB Plumbing Services410-636-6019
The Drain Guys240-848-4616
RL Cranford Plumbing301-855-7108
Prime Plumbing443-370-2373
All Things Plumbing LLC410-490-3354
United Backflow410-970-6988
Anchor Mechanical410-452-5601
AL Gleeson Electrical Co. Inc.301-440-7168
Jay Johnson Plumbing443-964-6992
Mechanical Engineer. & Construction443-200-1000
SS&R Mechanical410-907-7474
J&B Plumbing & Heating410-668-6510
JBA'S Plumbing202-629-6234
Patterson Plumbing & Mechanical LLC202-904-4346
Naumann Plumbing410-451-6199
Pro Stream Plumbing240-421-8095
Walls Plumbing & Heating410-535-2117
Acker and Sons Inc.301-897-0700
Drain Works301-437-1939
Madden Plumbing and HVAC Inc301-937-1000
SJT (Stephen J Tant Plumbing LLC)443-838-6864
Langenfelder Mechanical410-477-0400
1st Choice Plumbing443-790-9571
Metcalf Plumbing Service LLC410-242-3111
Unlimited Plumbing and Heating240-375-4945
A3 Mechanical Inc877-853-6201
Plumb Cheap Inc443-312-7229
Patriot Backflow & Gas, Inc.443-509-2738
Trade Works Plumbing410-970-3500
Complete Building Services (CBS)202-333-4977
HMJ Plumbing Service202-281-5414
D. Rob Enterprise410-982-8535
Clean Water Plumbing (CWP)410-259-9149
Ahoy Plumbing443-343-2920
Catons Plumbing, Drains410-247-0064
Walton & Company717-840-2222
Mech-Flow Corp.301-343-5705
Chesapeake Bay Plumbing443-249-5616
Arco Mechanical Serv. LLC410-908-8180
CRW Mechanical Inc.301-918-0056
Atlantic Mechanical410-484-4595
Perfect Plumbing LLC443-713-3135
24/7 Grease Trap & Services INC703-330-3491
The John E Ruth Co., Inc410-747-0678
Slo-Flo Plumbing443-734-8609
Welch & Rushe, Inc.301-430-6000
Clean Line Plumbing240-701-4326
Empire Plumbing202-438-4461
Plastech Services410-737-4700
WE Bowers & Assoc301-419-2488
Greig Plumbing443-332-8186
Dynamic Plumbing410-215-3634
Johnston Construction Company717-292-3606
GA Eberly Plumbing & Heating301-856-6900
JP Spadaro Plumbing301-779-4455
Lloyd Plumbing Corporation410-203-2720
Madison Mechanical Contracting LLC443-636-5192
TNT Plumbing & Drain Service LLC443-457-8228
Five Star Plumbing Service410-836-0118
Jeff Welch Plumbing, Inc.301-440-3027
Maryland Backflow Solutions (SLO-FLO)410-258-3196
Gabe's Plumbing LLC301-992-0522
Mitchell Plumbing & Heating Inc410-344-9320
Pro-Tech Mechanical Construction LLC410-877-2785
Saia Plumbing & Heating301-924-3600
American Combustion Industries INC301-779-3400
APX Plumbing & Heating LLC240-818-8155
RF Warder, Inc.410-344-0190
Palmer's Plumbing410-827-4546
Patuxent Plumbing and Mechanical, Inc.301-472-4010
Paramount Mechanical Corp703-369-7952
Greer Water Works410-439-8500
Amazing Plumbing Heating and Air410-864-9280
O'Connor Plumbing and Heating301-540-5050
Superior Mechanical Services, Inc301-931-0100
Flo-Tron Contracting443-463-5801
A&A Water Solutions LLC443-975-3724
Mechanical Plumbing Industries LLC240-309-0363
All Seasons Plumbing and HVAC301-277-1313
Woo Joo Mechanical LLC301-222-3277
Capital City Plumbing202-277-3664
Bluestream Services INC410-363-0072
JL Johnson and Sons Inc410-756-2780
Burco Plumbing518-225-4470
Defense Fire Protection410-766-7233
FTC (Ferguson Trenching Company)410-519-5700
Elite Plumbing & Home Services443-343-2284
CB Plumbing & Heating301-854-0609
QSP Plumbing Services Inc.301-453-6377
Summit Fire & Security410-787-0639
Wallace Plumbing202-531-8442
Premier Fire Protection Services240-366-8163
3-D Plumbing and Heating301-974-1128
Aegis Mechanical Corporation443-436-6001
Abbott Brothers Plumbing and Heating of MD410-256-2027
Abdul 's Plumbing Service202-841-8634
Delmar Plumbing & Heating Inc.301-482-1424
Shepherd Plumbing Inc (JW Shepherd)410-827-6778
B-Tek Plumbing & Heating410-721-8700
Stilwell Plumbing Inc.410-488-4545
Schaefer Mechanical Svcs Inc.410-876-6825
Guardian Plumbing Services301-261-7481
C&C Mechanical Contractors301-812-1385
Apperson Plumbing301-870-1022
First Call Plumbing, Inc.301-261-4605
Calvert Mechanical Solutions410-323-5400
Carter Quality Plumbing443-822-9214
Abend Services[cite: 5]410-609-0708
Nationwide Plumbing & Heating443-668-6702
Emjay Engineering & Construction Co. Inc.443-250-5397
McGuire Plumbing & Heating Inc410-355-2068
Blue Dot Services of MD410-736-0474
JA Smith & Company410-796-7532
James A Douglas301-922-8259
Maryland Sewer & Plumbing Services410-255-9300
JT Lawn Services LLC443-336-4297
Breeden Mechanical703-631-2711
API (Associates Plumbing Inc.)443-917-2500
Gladiator Plumbing443-726-3467
Walden Plumbing LLC443-994-8412
McDevitt & Sons Plumbing & Heating Inc.410-255-7474
North River Plumbing & Gas443-822-8547
Raymar Plumbing Service Inc301-772-7482
Robert A. Tull301-948-2490
Pinnacle Plumbing & Heating410-519-3747
Carson Plumbing410-963-0204
TL Brown Contractor LLC443-629-0278
Custom Quality Plumbing & Heating717-345-6157
Confer's Plumbing LLC443-694-4922
The Riverview Group Inc301-893-2300
CA Kamm Corporation410-798-4108
Robert G. Bookhultz Plumbing301-317-6706
Pinpoint Plumbing443-869-1522
TT Jones Plumbing423-677-2255
Roland H. Woelper Inc410-384-7755
Shoster Plumbing410-991-9387
T&D Plumbing & Heating Company410-242-8850
Earl Smith240-841-3474
The Plumber410-299-5318
Lawver Plumbing Co. LLC.443-250-4786
Tripp Plumbing, LLC410-349-7736
WA Booth Plumbing Service443-221-0957
LJC Plumbing & Heating Inc.410-850-5177
White Hall Plumbing & Hydronics410-557-9648
H&K Plumbing443-216-4309
Shelton Plumbing301-898-8880
Titan Mechanical & Plumbing571-292-1274
Charles A Klein & Sons410-549-6960
Linthicum Plbg & Drain Cleaning410-768-5350
Mid-Atlantic Water Services410-573-1020
Gartland Plumbing410-875-5303
Chesapeake Plumbing, Inc.410-437-3888
Climate Care HVAC Services410-921-3838
GH Nitzel410-335-0200
GE Tignall & Company410-666-3000
Holliday Plumbing Services LLC443-336-9406
Aronhalt Inspections & Services443-900-9192
Park Plumbing LLC443-539-6156
Mallick Plumbing Commercial Division240-238-1840
RE Robertson Plumbing & Heating410-266-0636
Tim Butler Plumbing & Heating410-590-7664
First Class Plumbing Inc410-571-0006
Scardina Plumbing & Heating410-761-6900
Water Doctor - Maryland Water Conditioning410-792-0327
All Star Plumbing LLC410-841-9214
Your Local Plumbing and Heating301-213-5172
Marino Plumbing (AWA)410-747-5616
Clarksville Plumbing410-386-3499
Staton Heating, Cooling & Plumbing410-263-5100
All Around Plumbing301-698-1028
A Better Plumber301-994-1000
RV Carey's Plumbing & Heating301-424-8899
B&D Plumbing Inc.301-595-1141
General & Mechanical Services LLC (GMS)410-349-4070
S and D Plumbing410-440-1094
Heil Plumbing410-799-7727
Ben Lewis Plumbing301-428-3900
Ben Bauman & Sons LLC410-796-2515
Chesapeake Plumbing & Heating302-732-6006

List updated on 10/15/2026