- Seaglaze Marine Windows Ltd
- Sealtech ApS
- Seasafe Systems
- SeaVsat
- SEBERT ENGINEERING GMBH
- SEC SHIP'S EQUIPMENT CENTRE BREMEN GmbH
- SEC Ship's Equipment Centre Groningen B.V.
- SEEKARTE KAPITAN A. DAMMEYER GmbH & Co. KG
- SES-X MARINE TECHNOLOGIES
- Shelquip Ltd
- SHIP EQUIP AS
- Shipham Valves Ltd
- Ships Electronic Services Ltd
- SIEMENS AG Industrial Solutions and Services Industrial Plants
- Siemens Nederland N.V. Bruinhof Marine
- SIGMA COATINGS Protective Coatings and Marine Business Unit
- Silentor A/S
- SIMRAD AB
- Simtronics ASA (Head office)
- Sino-European Marine Services GmbH
- SITINDUSTRIE MARINE SAS
- SKB Life Saving Equipment
- SKF Coupling Systems AB
- Sleev-it Fire Systems Limited
- SM ELECTRICS GmbH
- SMC - Ship Motion Control
- SMEDEGAARDEN
- Smith Flow Control Ltd.
- Soc Nouvelle ACEBI SA
- Societe Internationale des Moteurs Baudouin
- SODENA AS
- SOLAR SOLVE MARINE
- Solberg Scandinavian AS
- Somas Instrument AB
- Sondex BV
- Southern Marine Consult AS
- Sperre Rotterdam BV
- SPERRY MARINE A/S
- SPM Instrument BV
- SPRAYING SYSTEMS DEUTSCHLAND GMBH
- SPX Flow Technology Assen B.V.
- SPX Flow Technology Danmark A/S
- STA Schiffstechnik & Anlagenbau GmbH
- Stadt Automasjon AS
- STAHL Waschereimaschinenbau GmbH
- Star Instruments Ltd
- Statendam Steel Plates
- STC-Steyr Walzlager Deutschland GmbH
- STEINSVIK AS
- STENTO ASA
- Stone Marine Propulsion Limited
- STOP CHOC Schwingungstechnik GmbH
- STORK KWANT BV
- Stromag AG
- STS Sensoren Transmitter Systeme GmbH
- STT International Ltd.
- Sulzer Pumpen (Deutschland) GmbH
- Sun Marine Seats BV
- SURVITEC GROUP LIMITED
- Svend Hoyer A/S
- SYBERG AS
- T&E Engineering BV
- T-ISS Solastape BV
- TAMROTOR MARINE COMPRESSOS AS
- TAV Engineering Ltd
- TEAMTEC A/S
- TECHFLOW MARINE Ltd.
- Technical Service
- TECO MARITIME ASA
- Teekay Couplings Ltd.
- Teignbridge Propellers International Ltd
- TEMARO The Dutch Marine Suppliers
- TENMAT Ltd.
- Testo AG
- THANNER AND Co.
- THB Verhoef bv
- Theunissen Technical Trading BV
- THR Marine
- THRANE & THRANE A/S
- Thrustmaster Europe B.V. (TMEUR)
- Thyboron Skibssmedie
- Tideland Signal Ltd
- Tides Marine International Limited
- Tools & Pumps Trading Centre BV
- torbo Engineering Keizers GmbH
- Torque Marine IPS Innovative Propulsion Systeme GmbH & Co. KG
- Total Filtration Ltd
- TQ Enviromental Plc
- TQC GmbH
- TRAFA BV
- TRANSAS SCANDINAVIA AB
- TREADE AS
- Trelleborg Viking AS
- Trimat Ltd
- Tritex NDT Ltd
- TTS Handling Systems AS
- TTS Marine ASA
- TTS Syncrolift AS Shipyard Solutions
- Tufnol Composites Ltd
- Twin Disc International SA