| Guidance Care Center INC | Retail Trade | $1,066,833 | $1,081,295 | 123 | N/A |  Research |
| D'asign Source LLC | Professional, Scientific, and Technical Services | $903,800 | $911,407 | 62 | $14.4M | Research |
| Dolphin Research Center | Arts, Entertainment, and Recreation | $722,929 | $726,870 | 80 | $12.2M | Research |
| Marathon Sunset Inc. | Accommodation and Food Services | $718,341 | $721,115 | 76 | $13.5M | Research |
| Marathon Paradise INC | Accommodation and Food Services | $698,118 | $344,245 | 86 | $15.3M | Research |
| Keys Fisheries, Inc. | Retail Trade | $633,000 | $641,480 | 150 | $16.7M | Research |
| Discount Rock & Sand INC | Retail Trade | $424,800 | $426,287 | 65 | $13.4M | Research |
| Discount Rock & Sand, Inc. | Retail Trade | $421,100 | $423,902 | 38 | $5.9M | Research |
| Interselect INC | Accommodation and Food Services | $398,385 | $399,948 | 16 | <$5M | Research |
| Mirabella Seafood Company | Accommodation and Food Services | $351,311 | $353,371 | 43 | $7.6M | Research |
| Design Center INC | Professional, Scientific, and Technical Services | $337,843 | $341,812 | 25 | <$5M | Research |
| Design Center Inc. | Construction | $337,800 | $342,783 | 36 | $10.9M | Research |
| Jrc Pro Builders of the Keys LLC | Construction | $334,551 | $337,823 | 46 | $52.4M | Research |
| Superior Electric of the Florida Keys | Construction | $310,162 | $312,804 | 21 | $6.9M | Research |
| Marathon Garbage Service, Inc. | Administrative and Support and Waste Management | $302,400 | $306,415 | 43 | $8.1M | Research |
| Marathon Sunsets Inc. | Accommodation and Food Services | $284,600 | $286,315 | 75 | $13.3M | Research |
| Marathon Seawalls & Docks INC | Construction | $240,900 | $242,493 | 23 | $7.8M | Research |
| Keys Contracting Services INC | Construction | $239,270 | $240,991 | 18 | $5.5M | Research |
| Marathon Seawalls & Docks, Inc. | Construction | $236,800 | $238,556 | 25 | $5.8M | Research |
| Keys Contracting Services INC | Construction | $227,746 | $230,523 | 10 | $11.4M | Research |
| Florida Keys Lobster House INC | Accommodation and Food Services | $220,402 | $223,343 | 40 | $7.1M | Research |
| Cristian Landscaping & Lawn Service INC | Administrative and Support and Waste Management | $212,348 | $215,188 | 26 | $5.6M | Research |
| Sparky's Landing, INC | Accommodation and Food Services | $203,900 | $205,905 | 63 | $11.2M | Research |
| Peter Rosasco, Cpa, P.a. | Professional, Scientific, and Technical Services | $199,500 | $200,654 | 11 | <$5M | Research |
| Peter Rosasco, Cpa, P.a. | Professional, Scientific, and Technical Services | $199,500 | $200,414 | 13 | <$5M | Research |