Internet and communication at sea
Connectivity at sea has changed substantially since 2022. Many vessels on established routes now carry Starlink Maritime terminals delivering speeds that make video calls practical — a significant change from the shared 256 kbps VSAT connections that defined the previous decade. But VSAT on older tonnage remains the norm on a large share of the global fleet, and data allowances, company access policies, and the reality of shared bandwidth make connectivity planning still a relevant skill. This page covers what to expect, what your rights are, and how to stay connected with the least friction.
- · Starlink vessels — 50–200 Mbps down; video calls practical; ~30–40% of newbuild/recently-refitted vessels
- · Ka-band VSAT — 2–10 Mbps shared; voice calls practical; messaging reliable; most vessels built post-2015
- · Ku-band VSAT — 256 kbps–2 Mbps shared; messaging only at peak hours; common on older tonnage
- · Iridium / Inmarsat voice + email — minimum guaranteed; backup/emergency only on most vessels
VSAT — the legacy standard
Very Small Aperture Terminal (VSAT) using geostationary satellites has been the standard merchant-ship connectivity system since the mid-2000s. Geostationary satellites sit at 35,786 km altitude — the resulting signal latency (600–800 ms round trip) makes real-time gaming impossible and video calls choppy. Bandwidth is shared across all users on the vessel, and shipboard VSAT bandwidth is often also shared with operational data traffic (vessel tracking, cargo management, performance monitoring) which takes priority.
On a VSAT vessel, strategies that help:
- Schedule voice calls during off-peak hours — typically 0200–0600 ship's time when fewer crew are online.
- Use asynchronous messaging (WhatsApp, Telegram, iMessage) rather than real-time voice — they compress efficiently and tolerate latency.
- Download news, podcasts, and maps while on a fast port WiFi connection for offline consumption at sea.
- Compress photos before sending — a 12 MP camera photo is 3–6 MB; resizing to 1 MB before sharing saves meaningful bandwidth.
Starlink Maritime — the new norm on newer vessels
SpaceX Starlink's maritime offering entered commercial service in mid-2022. By early 2024, several thousand merchant vessels had been fitted. Low-Earth orbit (LEO) satellites at ~550 km altitude give latency of 20–50 ms and sustained bandwidth of 50–200 Mbps on the ship-side terminal, depending on sea state and the number of co-orbiting satellites in the beam.
On a Starlink vessel, connectivity is broadly comparable to a slow home broadband connection: video calls work reliably, streaming is possible, and upload speeds support sending reasonable- quality photos and voice messages in real time. Data allowances and company access policies still vary — confirm with the radio officer on joining day whether there is a crew allowance cap and what hours any speed throttling applies.
Iridium GO and satellite voice / SMS
Iridium's LEO constellation provides global satellite voice calls and SMS at slow data rates (2.4–9.6 kbps). Iridium GO terminals — handheld or portable units — are carried by some vessels as crew-communication supplements, by offshore vessels and yachts where full VSAT is uneconomical, and as emergency backup. The practical use cases are:
- Voice calls in areas where geostationary VSAT coverage is poor (high latitudes).
- SMS messaging as a reliable low-bandwidth alternative when the main VSAT terminal is offline.
- Emergency communication if the primary systems fail.
Iridium is expensive on a per-minute basis — check with the master or radio officer before using it for routine family calls.
Port WiFi and seafarer centres
Port calls are the connectivity reset most seafarers look forward to. Options typically available:
- Seafarer welfare centres — Mission to Seafarers, Stella Maris, Sailors' Society, Apostleship of the Sea, ITF seafarer centres, and ISWAN-affiliated clubs offer free WiFi, computer terminals, local SIM card assistance, and telephone calls in most major ports globally. Welfare helplines can locate the nearest centre.
- Port terminal WiFi — Many container and bulk terminals offer crew WiFi in the terminal building or at the gate. Quality varies from excellent to unusable. The ship's agent can advise.
- Local SIM card — An unlocked smartphone or mobile hotspot with a local data SIM is often the best option for a 24–72 hour port call. Pre-paid data SIMs are available in most port cities. Check roaming options on your home SIM — some plans include generous international data that activates in port.
MLC internet access rights
MLC 2006 Regulation 3.1 (accommodation, recreational facilities, food, and catering) was amended at the 2022 Special Tripartite Committee to include specific provisions on ship-to-shore communication. Standard A3.1 now requires:
- Seafarers must have access to reasonable ship-to-shore communication facilities, including telephone and internet access.
- Any charge for the use of these facilities must be reasonable and not used as a profit mechanism.
- Access must be available at all reasonable times, except where it conflicts with the safety and security of the ship.
The 2022 amendment entered into force for states that have ratified it. If your vessel's communication policy denies reasonable access or charges exploitative rates, this can be raised as an MLC complaint. See food and accommodation rights and the onboard complaint procedure.
Low-bandwidth tips for slow VSAT
- Use WhatsApp or Telegram for messaging and voice calls — both use efficient compression and handle poor connections better than most alternatives.
- Use Signal for encrypted calls if privacy is important — comparable bandwidth to WhatsApp.
- Set your email client to receive text only and batch-download attachments manually; turn off auto-download of images in messaging apps.
- Pre-download offline maps (Google Maps, Maps.me) for port cities before the port call.
- Schedule software updates (phone, laptop) for port calls or Starlink vessels — a background iOS update over VSAT can saturate the shared connection for hours.
- Use VPN carefully — VPNs add overhead and reduce already-limited throughput; on a VSAT connection, a VPN may halve effective speed.
Frequently asked questions
Does the MLC 2006 give me a right to use the internet at sea?
MLC 2006 Regulation 3.1.7 (as amended in 2022) requires shipowners to ensure seafarers have access to reasonable means of communication with their families, including telephone, email, and internet. The 2022 amendments to Standard A3.1 specify that reasonable access to ship-to-shore communication facilities must be provided to seafarers at all times when not contrary to safety requirements, and that any charge for crew communication must be reasonable. The amendment entered into force for ratifying states in 2024. In practice, access policy is vessel-specific — but the regulatory direction is clear.
What speed does a VSAT connection offer?
Legacy Ku-band VSAT installations on older vessels typically deliver 256 kbps–2 Mbps shared across the crew. Ka-band (the current generation) offers 2–10 Mbps shared. Both are shared across officers, crew, and sometimes the ship's operational data traffic, meaning individual effective speeds at peak hours are much lower. Upload speeds are typically a quarter of download. Video calls at acceptable quality require sustained 1 Mbps minimum — rarely achievable on shared VSAT. Voice-only calls over WhatsApp or Telegram typically work at 64–128 kbps.
How does Starlink on ships differ from home Starlink?
Maritime Starlink (Starlink Maritime or Starlink Flat High Performance) operates on Ku-band LEO (low Earth orbit) satellites and delivers significantly higher speeds than traditional geostationary VSAT — typically 50–200 Mbps download, 10–20 Mbps upload on a good day. Latency is also much lower (20–50 ms vs 600–800 ms on geostationary VSAT), which makes video calls practical. Maritime Starlink became commercially available in 2022 and was widely adopted on smaller and medium-sized vessels by 2023–2024. Availability on your specific vessel depends on when the company upgraded. Ask the radio officer on joining.
What can I do at port to get better internet access?
Shore-side options at most major ports include: seafarer centres (Mission to Seafarers, Stella Maris, ITF, ISWAN-affiliated clubs) which offer free WiFi and SIM card purchase facilities; port terminal buildings and agent offices which often have WiFi; and local SIM cards for mobile data (effective in port and within cellular range of the coast). An unlocked smartphone or a simple WiFi hotspot device plus a local data SIM can provide a significant speed improvement over shipboard VSAT for the duration of a port call. See welfare contacts at <Link href="/help/helplines">/help/helplines</Link> for seafarer centre locations.
Primary sources
- · ILO — MLC 2006 Regulation 3.1 and Standard A3.1 (accommodation and communication, 2022 amendments)
- · ILO — MLC 2006 Special Tripartite Committee — 2022 amendments (communication rights)
- · ITF — Seafarer communication rights guidance
See also
- · Food and accommodation rights (MLC Title 3)
- · Money management — wire transfers and remittance apps
- · What to pack — electronics list
- · Information for families of seafarers
- · Welfare helplines and seafarer centre locations
- · On-board complaint procedure
- · Mental health at sea — staying connected with family
- · MLC 2006 overview
- · Joining-day checklist — asking about internet access on day one
Disclaimer. Technology and vessel-specific policies change frequently. Speed figures are indicative and will vary by vessel, satellite provider, time of day, and sea conditions. MLC amendment entry-into-force dates vary by flag state. Verify with your company and the relevant maritime authority.