VMS for Fishing Vessels: What It Is and How to Choose a Satellite Device for Offshore Fleets in Asia

VMS for fishing vessels: a small device with big compliance consequences

A VMS for fishing vessels is a fixed onboard tracker that reads GNSS position and sends it by satellite to a fisheries monitoring centre, so regulators can see where a vessel is and whether it is fishing as licensed. Across Asia the rules differ by flag state, but the direction is the same: lower size thresholds, stricter uptime and heavier penalties. For owners and ship managers running offshore fleets, choosing the wrong unit now means more than a dropped signal. It can mean fines, a suspended licence and trouble at export. This guide explains how VMS works, where it is mandatory and how to choose a satellite device.

Key Takeaways:

• There is no single ASEAN VMS rule. Vietnam requires VMS from 15 m, Indonesia and Thailand use 30 GT, and the Philippine mandate is in legal flux as of September 2026.
• VMS is not AIS. It is a regulator-facing satellite system, and it is the one auditors and export markets rely on.
• Silent units are an enforcement target. Vietnam reported 2,098 vessels offline for more than 6 hours in mid-2026.
• Shortlist devices by flag-state approval, satellite coverage on your actual grounds, data handling, fault-response time and airtime cost.
• Starlink and crew wifi are not a VMS, though they can be a backup way to report position.

What is a fishing vessel monitoring system, and how does it differ from AIS, LRIT and SSAS?

A fishing vessel monitoring system (VMS) is a regulator-controlled satellite tracking programme: a sealed onboard unit sends vessel identity, position, course and speed to a fisheries monitoring centre. AIS is an open collision-avoidance broadcast, while LRIT and SSAS are SOLAS systems for merchant-ship tracking and security alerts. They are not interchangeable.
According to Global Fishing Watch, AIS is required mainly on industrial vessels above 300 GT, while flag states generally set lower size thresholds for VMS. That gap explains why a 20 m trawler may barely appear on AIS yet be tracked closely by its fisheries authority.
Every VMS unit does two jobs. It fixes position from a GNSS constellation such as GPS, GLONASS, Galileo or BDS, and it relays that position over a communications link. For offshore fleets the link is normally satellite. Cellular only works near the coast, and HF, VHF or MF radio depends on shore station coverage.
One practical point for ship managers: in most regimes the VMS feed belongs to the authority, not to you. Ask any provider whether you also get owner-side access to the same positions and alerts.

Which fishing vessels must carry VMS in Southeast Asia and beyond?

There is no single ASEAN VMS rule. Each flag state sets its own threshold: Vietnam requires VMS on fishing vessels of 15 m and above, while Indonesia and Thailand use 30 GT. Vessels fishing in tuna RFMO areas or supplying the EU face further VMS-related obligations. Always verify with your fisheries authority.

The Philippine case shows why regional fleets should not treat national law as the only driver. The Coalition for Fisheries Transparency points out that WCPFC and IOTC both mandate VMS, and that the EU IUU Regulation uses VMS data in flag State verification and may request raw VMS records for consignments entering the European market. A vessel that fishes tuna or supplies EU buyers still needs a working, verifiable VMS whatever happens in domestic courts.

What happens when a VMS goes silent offshore?

Consequences depend on the flag state, but Vietnam shows how strict enforcement can get. Under Decree 41/2026/ND-CP, a master must report position at least every 6 hours by other means when VMS fails at sea, and return to shore within 10 days if it cannot be fixed. Penalties can reach VND 300 million plus licence suspension.
The decree, effective 25 January 2026, also requires the unit to run 24/7 including at berth in a fishing port, to be lead-sealed, and to be limited to two devices per vessel with only one recorded at a time. Data must be stored for at least 36 months on servers in Vietnam, unaltered and encrypted in transit. Providers must fix technical faults within 48 hours and give 30 days' notice before a service expires.
As reported by Báo An Giang, Decree 246/2026/ND-CP of 29 June 2026 sets fines of VND 30 to 40 million for a vessel of 15 to under 24 m that fails to report position, and VND 100 to 300 million for not maintaining data transmission, disabling the unit or sailing without one, with licence and master's certificate suspended for 6 to 12 months. At roughly VND 26,000 per US dollar, our approximate conversion is US$1,150 to 1,550 and US$3,850 to 11,550.
Enforcement pressure is real. At the national IUU steering committee meeting on 28 July 2026, the Ministry of Agriculture and Environment reported that 99.6% of vessels of 15 m and above carry VMS, yet 2,098 vessels had been offline for over 6 hours and 292 for over 10 days, according to the Vietnamese Government's news portal. The Deputy Prime Minister asked officials to separate technical faults from deliberate disconnection. For owners, a flaky unit means explaining each dropout.
Vietnam is not alone. Thailand's Department of Fisheries notes that Port In-Port Out officers inspect VMS signals when vessels enter and leave port.

How to choose a satellite VMS for fishing vessels: 7 criteria for offshore fleets

Choose a satellite VMS by checking, in order: flag-state approval, satellite coverage on your real grounds, reporting capability, physical durability, data handling, written fault-response times and total airtime cost. Cellular and radio can supplement the satellite link, but the satellite link is the baseline. The table turns each point into a question for suppliers.

For ship managers the seventh criterion is often decisive. A fleet dashboard can flag a unit that has been quiet for three hours, well before it reaches a 6-hour reporting threshold. The master then has time to act, instead of learning about a violation after the trip.
Fleets that fish under more than one authority should also ask whether one unit can report to both the flag state and a coastal state or RFMO, since some regimes may require it.

Where does MarineConnect IoSAT fit for fishing and offshore fleets?

MarineConnect IoSAT is a satellite VMS and IoT gateway that combines multi-constellation GNSS with the IDP/Viasat L-band network and needs no cellular SIM. It sends position, power status and SOS alerts to the MarineConnect platform, and suits fishing vessels and other assets operating beyond mobile coverage.
IoSAT runs on 12 to 30 VDC, is rated IP68, measures 162 x 145 x 49 mm and weighs 430 g. It supports GPS, GLONASS, Galileo and BDS, and offers 2 digital inputs, 2 outputs and 4 analog inputs for reading supply voltage, engine state or sensors. Digital input DI1 can be configured as an SOS button with a fast send cycle, while heartbeat and periodic messages use store-and-forward.
The design reflects pain points MarineConnect has compiled from fishing communities in Vietnam: weak mobile coverage offshore comes up repeatedly, and many older skippers are wary of operating digital equipment. So the unit should run without configuration during a trip.
On installation, our technicians power the unit, place it with a clear sky view away from RF interference, then check five things: GPS fix, the satellite TX Allowed status, a readable supply voltage, correct DI, DO and AI states, and a test message. Configuration happens on site over the Wi-Fi access point and web UI, with no need to remove the unit from the vessel.
Ashore, the MarineConnect platform stores raw payloads, decodes them, and shows maps, alerts and track history. A REST API lets a management company pull the data into its own systems.
A frank point: a unit used to meet a legal VMS obligation must come from a provider that the relevant authority has approved. For IoSAT or any other product, ask for the type-approval paperwork and confirm how data reaches the national monitoring centre before you sign.
IoSAT also does not replace shipboard internet. The two layers complement each other: VMS handles tracking and alerts, while Starlink Maritime with a SmartBox Gateway brings internet, crew wifi and IoT aboard. See our page on Starlink internet for boats and ships and the wider range of MarineConnect ICT services.

FAQ: VMS for fishing vessels in Asia

Is VMS mandatory for fishing vessels in Southeast Asia?

It depends on flag state and vessel size. Vietnam requires VMS from 15 m, and Indonesia and Thailand apply a 30 GT threshold. In the Philippines the national mandate was declared unconstitutional in January 2026 and remains under reconsideration, yet tuna RFMO rules and EU import checks still rely on VMS data. Confirm the current position with your fisheries authority before each licence renewal.

What is the difference between VMS and AIS?

VMS is a regulator-controlled satellite system, while AIS is an open broadcast built for collision avoidance. Global Fishing Watch notes AIS is mandated mainly for industrial vessels above 300 GT, whereas VMS thresholds are lower. Some vessels carry both, and combining the tracks gives a finer picture. Neither replaces the other for compliance.

Can Starlink or crew wifi replace a VMS?

No. Starlink and crew wifi are internet links, whereas a VMS is a sealed tracking unit that must meet the flag state's technical requirements and reach the authority's monitoring centre. A separate satellite internet link can still be another way to report position if the VMS fails. Ask your authority which channels it accepts.

How often must a VMS report position?

It varies by regime. Vietnam's Decree 37/2024/ND-CP set a floor of 12 positions per day at 2-hour intervals, with an alert at least one nautical mile before a restricted area, and Decree 41/2026/ND-CP points to its own updated appendix. RFMOs and other states set their own rates, so ask your provider for a compliance matrix covering every area you fish.

How long must VMS data be stored, and where?

In Vietnam, at least 36 months on servers located in Vietnam, unaltered and encrypted in transit, under Decree 41/2026/ND-CP. Other states set different rules on retention and hosting. Before signing, ask the provider where data is hosted, how long it is kept and how you can export a vessel track for an inspection or dispute.

Need help choosing VMS for fishing vessels or satellite tracking for your fleet?

Every fleet has its own routes, flag states and reporting duties. The MarineConnect engineering team can review your fishing grounds, power supply, installation points and fleet-management needs with you before you commit to a VMS for fishing vessels. If your vessels already suffer repeated dropouts, send us the vessel type, operating area and current unit and we will assess it quickly. You can also email [email protected].

🛰️ Talk to a MarineConnect engineer about satellite tracking and VMS for your fleet: contact the MarineConnect team