- Agency On Aging
- Air-Lert
- Aire-Ride Pittsburgh North
- Al Brochetti
- Al Gladys Specialty Vehicle
- Alberta Beardsley
- All The Moor Salon & Spa
- Allegheny Ear Nose & Throat
- Allegheny Graphics
- Allegheny Hydro Partners
- Allegheny Investments LTD
- Allegheny Mariner
- Allegheny Real Estate
- Allegheny Valley Land Trust
