| ADVANCED MICROSYSTEMS, INC. | — | 19972236 D | 1997-04-11 | Active | LEWISTON |
| ADVANCED MODIFICATIONS, INC. | — | 20110804 D | 2011-02-24 | Dissolved | WINDHAM |
| ADVANCED MODULAR SOLUTIONS, INC. | — | 19950559 F | 1995-03-07 | Withdrawn | AUGUSTA |
| ADVANCED MOLDING CONCEPTS, INC. | — | 19972308 D | 1997-04-23 | Suspended | PORTLAND |
| ADVANCED MORTGAGE SERVICES, LLC | — | 20070112FC | 2006-09-14 | Canceled | AUGUSTA |
| ADVANCED NATIONWIDE MESSAGING CORPORATION | — | 19950314 F | 1994-11-14 | Withdrawn | AUGUSTA |
| ADVANCED NETWORK MANAGEMENT INC. | — | 20220854 F | 2022-03-31 | Active | AUGUSTA |
| ADVANCED NURSING RELIEF, INC. | — | 20031965 D | 2003-04-23 | Dissolved | AUBURN |
| ADVANCED NUTRIENTS US LLC | — | 20120358FC | 2011-12-19 | Active | AUGUSTA |
| ADVANCED NUTRITIONAL HEALTH LLC | — | 20112744DC | 2011-03-28 | Dissolved | HOPE |
| ADVANCED ORTHOPAEDICS AND SPORTS MEDICINE, LLC | — | 20081924DC | 2007-12-20 | Canceled | SOUTH PORTLAND |
| ADVANCED ORTHOPEDIC MEDICINE, LLC | — | 20100307FC | 2009-11-30 | Withdrawn | READFIELD |
| ADVANCED PAINTING INC. | — | 20071332 D | 2007-02-27 | Active | WINDHAM |
| ADVANCED PATIENT ADVOCACY, LLC | — | 20090090FC | 2008-08-18 | Withdrawn | AUGUSTA |
| ADVANCED PATIENT ADVOCACY, LLC | — | 20120219FC | 2011-10-14 | Withdrawn | AUGUSTA |
| ADVANCED PAVING TECHNOLOGIES, LLC | — | 20063385DC | 2006-05-04 | Dissolved | GORHAM |
| ADVANCED PAYROLL SYSTEMS, INC. | — | 20170280 F | 2016-10-11 | Withdrawn | YORK |
| ADVANCED PEST SOLUTIONS L.L.C. | — | 20219067DC | 2021-04-09 | Active | LITCHFIELD |
| ADVANCED PETROLEUM PRODUCTS COMPANY, INC. | — | 19910054 F | 1990-08-03 | Withdrawn | AUGUSTA |
| ADVANCED PHARMA, INC. | — | 20160177 F | 2015-09-04 | Withdrawn | AUGUSTA |
| ADVANCED PHARMA, INC. | — | 20180198 F | 2017-09-25 | Merged | AUGUSTA |
| ADVANCED PHARMA/BOTANICS | — | 19952667 D | 1995-06-19 | Suspended | PORTLAND |
| ADVANCED PHARMACEUTICALS, LLC | — | 20180668FC | 2018-02-09 | Canceled | — |
| ADVANCED PHARMACY CONCEPTS, LLC | — | 20211377FC | 2021-04-20 | Active | PORTLAND |
| ADVANCED PHARMACY, LLC | — | 20150076FC | 2014-08-01 | Active | CHELSEA |
| ADVANCED PHYSICAL THERAPY, L.L.C. | — | 20040500DC | 2003-09-12 | Active | AUGUSTA |
| ADVANCED PLASTERING & DRYWALL, INC. | — | 20051360 D | 2005-01-13 | Dissolved | SEBAGO |
| ADVANCED PLUMBING | — | 20070480 D | 2006-10-10 | Dissolved | BOWDOIN |
| ADVANCED POOLS, INC. | — | 20011673 D | 2001-03-05 | Dissolved | AUBURN |
| ADVANCED POWER CONTROL, LLC | — | 20170082FC | 2016-08-02 | Inactive | AUGUSTA |
| ADVANCED POWER TECHNOLOGIES, LLC | — | 20100412FC | 2010-01-28 | Withdrawn | — |
| ADVANCED PRACTICE SOLUTIONS, LLC | — | 20247550DC | 2023-06-12 | Dissolved | MERCER |
| ADVANCED PRESERVATION SOLUTIONS LLC | — | 20173451DC | 2017-01-19 | Dissolved | SACO |
| ADVANCED PRODUCT FINISHING, INC. | — | 19940913 D | 1993-11-22 | Suspended | PORTSMOUTH |
| ADVANCED PRODUCTS COMPANY USA, LLC | — | 20112789DC | 2011-04-06 | Active | KENNEBUNK |
| ADVANCED PROJECT SOLUTIONS, LLP | — | 20210005FP | 2021-04-27 | Active | PORTLAND |
| ADVANCED PROPERTIES, LLC | — | 20052206DC | 2005-02-01 | Dissolved | PORTLAND |
| ADVANCED PROPERTY CARE, LLC | — | 20052790DC | 2005-03-21 | Dissolved | PORTLAND |
| ADVANCED PROPERTY MAINTENANCE COMPANY, LLC | — | 20071457DC | 2006-11-29 | Dissolved | AUGUSTA |
| ADVANCED PROPERTY MANAGEMENT, LLC | — | 20171263DC | 2016-09-19 | Dissolved | BIDDEFORD |
| ADVANCED PROTECTION PRODUCTS INTERNATIONAL, INC. | — | 20190023NF | 2018-11-05 | Active | AUGUSTA |
| ADVANCED QUALITY CUSTOM HOMES LLC | — | 20031885DC | 2003-03-31 | Active | — |
| ADVANCED QUALITY HOMES, LLC | — | 20071049DC | 2006-10-16 | Inactive | FARMINGTON |
| ADVANCED RADIO TELECOM CORP. | — | 19970088 F | 1996-07-29 | Withdrawn | AUGUSTA |
| ADVANCED RADIO TELECOM CORP. | — | 19970587 F | 1996-12-23 | Withdrawn | AUGUSTA |
| ADVANCED REALTY MANAGEMENT, LLC | — | 202611191DC | 2026-02-24 | Active | TURNER |
| ADVANCED RECEIVABLE SOLUTIONS, INC. | — | 20040687 F | 2004-02-26 | Withdrawn | AUGUSTA |
| ADVANCED RECOVERY SOLUTIONS, LLC | — | 20071663DC | 2006-12-14 | Dissolved | LEBANON |
| ADVANCED RECOVERY SYSTEMS, INC. | — | 202500774 F | 2025-02-10 | Active | AUGUSTA |
| ADVANCED REFRESHMENT SYSTEMS, INC. | — | 19831905 D | 1983-06-29 | Suspended | AUBURN |