| ASSUREDPARTNERS NEW ENGLAND, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Dec 21, 1978 | Active |
| GALLAGHER BASSETT SERVICES, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Jul 22, 1985 | Active |
| GALLAGHER RE INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Nov 18, 1993 | Active |
| BOLLINGER, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Dec 4, 1995 | Active |
| BOON ADMINISTRATIVE SERVICES, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Dec 13, 2000 | Active |
| GALLAGHER BENEFIT SERVICES, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Jan 25, 2002 | Active |
| GBS INSURANCE AND FINANCIAL SERVICES INCLocation not reported, CT · Active | Location not reported, CT | Corporation | Jul 23, 2002 | Active |
| Cadence Insurance, Inc.Location not reported, CT · Withdrawn | Location not reported, CT | Corporation | Oct 10, 2003 | Withdrawn |
| MOURNING PARENTS ACT, INC.Portland, CT · Active | Portland, CT | Corporation | Jan 22, 2004 | Active |
| ARTHUR J. GALLAGHER RISK MANAGEMENT SERVICES, INC.Location not reported, CT · Withdrawn | Location not reported, CT | Corporation | Jun 10, 2005 | Withdrawn |
| INSENTIAL, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Mar 30, 2007 | Active |
| Gallagher Affinity Insurance Services, Inc.Location not reported, CT · Active | Location not reported, CT | Corporation | Nov 7, 2007 | Active |
| TOMPKINS INSURANCE AGENCIES, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Oct 20, 2008 | Active |
| FRED C. CHURCH, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Dec 16, 2011 | Active |
| RISK PLACEMENT SERVICES, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Apr 28, 2014 | Active |
| ASSUREDPARTNERS, INC.Location not reported, CT · Withdrawn | Location not reported, CT | Corporation | Jun 26, 2014 | Withdrawn |
| Gallagher Risk Management & Insurance Services, Inc.Location not reported, CT · Active | Location not reported, CT | Corporation | Mar 9, 2015 | Active |
| WOODRUFF-SAWYER OREGON, INC.Location not reported, CT · Withdrawn | Location not reported, CT | Corporation | Jun 20, 2016 | Withdrawn |
| KEENAN & ASSOCIATES, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Jun 3, 2020 | Active |
| Accretive Insurance Solutions, Inc.Location not reported, CT · Active | Location not reported, CT | Corporation | Aug 23, 2022 | Active |
| SYNERGY PROFESSIONAL ASSOCIATES, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | May 8, 2023 | Active |
| National Insurance Services of Wisconsin, Inc.Location not reported, CT · Active | Location not reported, CT | Corporation | Aug 23, 2023 | Active |
| THE BOON INSURANCE AGENCY, INC.Location not reported, CT · Active | Location not reported, CT | Corporation | Mar 13, 2026 | Active |