MDplates.com
MDplates is a joint venture between Jordan Irazabal of Delaware, and Scott Zillmer of Maryland. The goal is to find and photograph every special organization plate that Maryland offers.
Letter: S
| Type | High | Full Name |
| SA | 0022 | St. Andrew's Society of Baltimore |
| SAF | 0021 | Maryland Division of the Society of American Foresters |
| SAI | 0046 | Pride of Balitmore Chorus |
| SAL | 0176 | Sons of the American Legion |
| SAR | 0128 | Maryland Society Sons of the American Revolution |
| SB | Stanton Bates Alumni Association, Inc. | |
| SC | St. Charles Sportsman's Club, Inc. | |
| SCA | 0040 | Spelman College |
| SCC | Stoney Creek Fishing & Hunting Club, Inc. | |
| SCF | 0029 | Salisbury Career Fire Fighters |
| SCP | Saint Clare Parish | |
| SCS | 0043 | South Carolina State University National Alumni Association |
| SD | 1834 | Maryland Scuba Association, Inc. |
| SDV | Second District Volunteer Fire Department and Rescue Squad, Inc. | |
| SF | Special Forces Association | |
| SFA | St. Frances Academy Association | |
| SFD | Secretary Volunteer Fire Company | |
| SFO | Secular Franciscan Order | |
| SFT | Shaft Fire Department | |
| SG | Southern Garrett County Rescue Squad, Inc. | |
| SGK | 0486 | Susan G. Komen for the Cure |
| SGR | Sigma Gamma Rho Sorority, Inc. | |
| SH | 0196 | Snow Hill Volunteer Fire Company |
| SHC | 0072 | Susquehanna Hose Company |
| SIG | 0093 | Frank J Battaglia Signal 13 Foundation, Inc. |
| SJ | 0078 | St. James School |
| SJC | St. Johns Alumni Association | |
| SK | 0082 | Stockton Volunteer Fire Company |
| SKI | Baltimore Ski Club, Inc. | |
| SL | St. Leonard Volunteer Fire & Rescue Company Seven | |
| SM | 0095 | St. Mary's College of Maryland Alumni Association |
| SMD | 0036 | Society of Mayflower Descendants in the State of Maryland |
| SMF | 0024 | St. Michaels Fire Department Inc. |
| SML | Chesapeake Heritage Conservancy | |
| SMT | 0340 | Maryland Chapter of the National Flight Paramedics Association |
| SN | 0145 | Society of Senate's Past |
| SN | Sons of Norway | |
| SO | Special Olympics Maryland | |
| SOF | Spirit of Faith Christian Center | |
| SOM | 0245 | University of Maryland School of Medicine |
| SP | 038 | St. Paul's College National Alumni Association, Inc. |
| SPC | Sparrows Point Country Club, Inc. | |
| SPG | St. Paul's School for Girls Alumnae Association | |
| SPH | Most Worshipful Prince Hall Grand Lodge F. & A. M. | |
| SPS | 0003 | St. Paul's School |
| SQ | 0249 | Mason Dixon Square Dancers Federation, Inc. |
| SR | 0560 | Ancient and Accepted Scottish Rite of Freemasonary |
| SRF | 0100 | Ocean City Chapter Surfrider Foundation |
| SRT | 0074 | Ocean City Beach Patrol |
| SS | 209 | Delegates Past (House of Delegates) |
| SS | 0089 | Silver Spring Volunteer Fire Department, Inc. |
| SS | 178 | The Speaker's Society |
| SSA | 0010 | Maryland Saltwater Sportfishermen's Association, Inc. |
| SSM | Street Survivors of Maryland | |
| SSS | Sisters Surviving | |
| SSU | 0121 | Salisbury State Univ |
| ST | Next Generation Space Telescope | |
| STC | University of MD Medical System Foundation | |
| STC | 0831 | University of MD Shock Trauma |
| STF | 0123 | Steamfitters Local 602 |
| SU | 0139 | Salisbury University Alumni Association |
| SU | 00007 | Syracuse University Alumni Club of Washington DC , Inc. |
| SUA | 0049 | Southern University Alumni |
| SUV | 0032 | Sons of Union Veterans of the Civil War |
| SV | Solomons Volunteer Rescue Squad & Fire Department, Inc. | |
| SV | 0122 | US Submarine Veterans |
| SVF | 0054 | Showell Volunteer Fire Department |
| SWM | 0018 | U.S. Masters Swimming |
| SX | 0025 | Singerly Fire Company |
| SY | Sykesville - Freedom Fire Department | |
| SYK | 0074 | Town of Sykesville |
