The predominant microorganisms that cause subclinical and clinical intramammary infections (IMI) can vary with environmental conditions, personnel, and management practices. However, limited information exists regarding the types of organisms isolated from subclinical IMI of dairy cattle in the southeast United States. To address this limitation, 5 certified organic herds in KY and TN that were participating in Dairy Herd Improvement programs and willing to participate were enrolled in the study. The top 10–20 cows in the herd with the highest SCC according to the most recent DHI test were selected for sampling at each farm visit (4–6 times per year, Mar 2017 to Nov 2017). Quarter milk samples were collected aseptically and stored at −20C until cultured. Culture and organism identification were performed as outlined by NMC. Overall, 168 cows and 1,230 quarters were sampled. Of these, 27 (2.1%) were considered contaminated with either bacillus or 3+ colonies of different morphology and 685 (55.7%) exhibited no growth. After removing these samples, 518 quarter samples contained 1 (92%) or 2 (8%) bacterial isolates. The dominant organisms isolated included coagulase-negative staphylococci (CNS; 26.2%), Staphylococcus aureus (17.0%), Staphylococcus hyicus (15.4%), Corynebacterium bovis (12.1%), and Streptococcus uberis (10.2%). Closer examination of a subset of CNS isolates, revealed 67 of 106 (63%) were Staphylococcus chromogenes. Corynebacterium species other than C. bovis and Streptococcus dysgalactiae accounted for 2.5 and 3.5% of the isolates, respectively. The predominant species on each farm varied considerably, with CNS and S. aureus most frequently isolated on 2 herds, CNS and S. hyicus on a third, C. bovis and S. uberis on a fourth, and CNS, C. bovis and S. aureus on a fifth. This suggests local environments and management practices significantly influence dominant types of organisms associated with IMI. Strategies to prevent or minimize new infections with these organisms should be a part of mastitis control programs on organic dairy farms in the southeast US.