With Starlink’s high-speed internet, do sailors still need satellite phones on board while at sea? Ali Wood looks at the pros and cons
of the different systems available to cruisers

Satellite communication at sea: staying connected from your boat

Satellite phones, which connect with mobiles and landlines via Earth stations, have changed little since I first wrote about them in 2006.

At the time I attended a publicity stunt at the Southampton Boat Show where Dee Caffari’s boyfriend called her in the Southern Ocean to discuss (rather disappointingly) the weather.

The previous year I’d been at a press conference in which Bob Geldof called Ellen MacArthur on B&Q, addressing her with a far more entertaining, “Hi sexy.”

Though Geldof’s plan to send sailors across the Channel to end poverty wasn’t entirely clear, the phone signal was.

It was hard to believe his voice had travelled 22,000 miles to a satellite, pinged back down to a land station and back to the phone, sounding as crisp as if it had gone two miles to the telephone exchange.

A man standing by a starlink dish on a boat

Although satellite communication has changed little over the years, Starlink has made low-cost, high-speed internet a reality on board. Credit: Ali Wood

Since then Dee Caffari has sailed around the world six times, Ellen MacArthur has set up two groundbreaking charities, and telephone exchanges are being phased out for full-fibre internet.

However, satellite capabilities have changed little.

According to comms expert Ed Wildgoose, sat phones still “sound the same, look the same and cost the same, if not more.”

But what is revolutionising communication at sea is Elon Musk’s Starlink, which provides a low-cost, high-speed internet service that makes web browsing, video streaming and WhatsApp calls readily accessible to leisure boaters.

Which satellite network?

Satellites used for TV, telephone, radio and internet work by relaying and amplifying radio signals.

Geostationary ones (GEOs) remain at the same position relative to the Earth, at about 22,000 miles altitude. Because of their height, their coverage (footprint) is greater.

A man waving from a boat

Henrik Linder was dismasted a week after leaving Gran Canaria on ARC+ 23. Thanks to his Starlink he was able to message other boats. Credit: James Mitchell

Low Earth Orbiting satellites (LEOs), on the other hand, orbit the planet at around 900 miles or less and because of their smaller footprint, a greater number of satellites is needed to provide continuous coverage.

In between, you have Middle Earth Orbit (MEO), at about 6,400 miles, which is where navigational satellites such as GPS and Galileo reside.

However, satellite communications are largely handled by LEO and GEO.

Satellite communication: GEO satellites

British telecoms company Inmarsat uses just three satellites for voice and data, each with a single spot beam that covers up to one-third of Earth’s surface with the exception of the polar regions.

Thuraya, meanwhile, covers Europe, North Africa and the Middle East. These highly reliable networks allow internet and phone calls (voice data) to be made at sea.

Launched in the 1980s, GEO satellite technology is effective, but a significant drawback is the 44,000 miles a signal needs to travel from a GEO satellite to your boat’s antenna and back, resulting in a high latency (‘lag’ or ‘ping’) of at least 250 milliseconds (ms) each way.

In rural and remote locations, GEO satellite broadband internet has long been the solution where terrestrial broadband is too slow.

LEO satellites Iridium is the only satellite network that offers total global coverage. Its 66 LEO satellites orbit at 485 miles of altitude, and pass overhead every nine minutes, automatically handing over to the next satellite.

With Iridium, line drops are rare as long as you have a strong signal and a clear view of the sky.

A map of the work showing the satellite coverage from Iridium to provide satellite communication for sailors

How Iridium’s constellation of LEO satellites gives coverage over the whole planet. Credit: Iridium

Globalstar has 25 satellites. Its Duplex coverage (which is used by GSP-1600 and GSP-1700 phones) includes most of Europe and the Caribbean, though not the Atlantic. The Canary Islands sit on the practical limit of the European coverage area. Globalstar’s SPOT coverage, however, covers most of the Earth’s surface area, including the Atlantic.*

The satellite network that’s creating the most buzz, however, is Starlink.

Orbiting at 340 miles altitude, these small satellites launched by Elon Musk’s company SpaceX, can easily handle the explosive demand for bandwidth.

Orbiting on the same orbit as the International Space Station, they take 90 minutes to circle the Earth, moving in and out of range.

Because of this, thousands are required to provide uninterrupted coverage.

A drawing of a satellite

An example of Iridium’s satellite vehicles. Credit: Iridium

Starlink currently has over 6,000 satellites, while its closest competitor Eutelsat OneWeb – which is more government and enterprise focussed – has 648.

Both have polar-orbiting satellites in their fleets, allowing claims of (potentially) global coverage.

The downside to LEOs is they have a much lower lifespan than GEOs due to the harsher environment, suffering radiation and atmospheric drag; maintaining them is an expensive business.

“Satellite internet is a graveyard of previous attempts,” says Ed Wildgoose, founder of MailASail, a satellite communication supplier to the marine and aviation sector.

“The estimate as to how much Elon Musk has spent is not clear, but some say $8 billion… and everything that money has built will fall out of the sky in three to five years.”

Satellite communication: Bandwidth and ping

Because of their lower orbit, LEO satellites allow much more bandwidth – the amount of data uploaded or downloaded (measured in megabits per second or ‘mbps’).

In addition, you can expect faster ping (the amount of time that information takes to travel). Ideally, you want the lowest ping and the highest upload and download speeds.

There’s much debate as to what constitutes a ‘good’ internet speed but as a rule of thumb, a download of at least 100mbps and upload of 10mbps is fast enough to handle most online activities.

A man wearing a white T-shirt and glasses on a boat

Ed Wildgoose helping customers at the start of the ARC rally. Credit: James Mitchell

Bearing in mind fast UK broadband has download speeds of 230mbps (test yours at speedtest.net), you can see how slow 2.4kbps might feel on an old Iridium satellite phone.

Similarly, as any online gamer will tell you, when ping is too high, the game will register the other player’s move first, meaning you suffer the headshot before getting a chance to react!

Virgin Media cites a good ping speed as 10-20ms for professional gamers, and a ‘perfectly average’ ping as 20-50ms.

Of course, most sailors aren’t playing Call of Duty in the Atlantic, and if the purpose of your satellite device is to make a distress call, Iridium’s high-quality Certus system offers a ‘reasonable’ latency of around 500-600ms.

Theoretically, you could use it for troubleshooting engine failure over video, though cost-wise you’d be far better off buying data from Starlink.

The future of satellite communication

Recognising the limitations of its data-only offering, in January 24 SpaceX launched six new Starlink satellites and announced plans for a ‘Direct to Cell’ service, through specific mobile carriers such as T-Mobile.

Right now this is being trialled with text messages, and voice call functionality is due to come in 2025, though it’s not clear whether this will be at an additional cost to Starlink’s usual package, and sold through the third party.

A table showing satellite networks

Amazon’s high bandwidth ‘Project Kuiper’ is planning to launch its 3,000 LEO satellite constellation later this year, rolling out the commercial service in 2025, which is designed to bring ‘fast, affordable broadband to unserved and underserved communities around the world’.

Some leading satellite companies are investing in multi-orbit strategies, combining higher capacity GEO satellites with LEO and MEO satellites to support global demand for high-speed connectivity.

For example, Inmarsat states its Orchestra network will combine GEO, LEO and terrestrial 5G.

Why bother with a sat phone?

For high data use, Starlink is the best value satellite internet provider at sea.

So if you can use it for video calls, why bother with a traditional satellite phone? The answer is reliability.

Whilst you can make calls with Starlink, these are wifi calls, powered by a technology known as VoIP (Voice over Internet Protocol), using applications such as Skype and WhatsApp.

Satellite phones, on the other hand, have ‘direct to cell’ or ‘voice’ capabilities, meaning you can use an Iridium or Inmarsat satellite phone to speak on mobile phones and landlines, just like you would on land with ‘normal’ cellular (short-range radio) data.

A satellite phone

Satellite phones, like the Iridium Extreme handset, are still the most reliable ways to stay in touch at sea

The reason for the speed difference between Starlink and traditional sat phones is how they operate and the frequencies they use.

So, for example, Iridium should work (comparatively slowly) in all weathers, whereas Starlink is more likely to work really fast most of the time and then perhaps not work at all when you are in a storm.

Ed Wildgoose explains that Elon Musk bought lots of relatively cheap radio spectrum while the traditional satellite companies went after ‘safety of life reliability’, buying only a sliver of bandwidth in the highly competitive space where mobile phones normally live.

“Compare your mobile phone to satellite TV,” he says. “You’re used to your mobile phone working when it’s foggy, right? But when it rains heavily, most people can identify with the disruption to Sky TV. Relatively cheap, high-frequency spectrum like that of Starlink has the same disadvantage.”

That said, Wildgoose acknowledges Starlink’s appeal. “Starlink has been very compelling for many people. Yes, you might pay £80 a month for an old-style Iridium and get basic emails and a tiny bit of data, or for £100 more you’re talking Netflix. It’s quite a step up. What people miss, though, is safety of life reliability. If I was in distress in the middle of the Atlantic and instead of making a phone call I could make a Zoom call, it’s not a terrible idea, but this product is not intended to be reliable or to work on a given day. It’s intended to be mass market – tons of data for a relatively low price. I wouldn’t trust my life to it and you’d be well advised to have some sort of backup system.”

Entertainment vs safety

In the past, we’ve tended to lump safety communications (ie calling for help from a sinking ship) and satellite receivers (the equipment needed to do this) as the same thing, with the added benefit of being able to transmit your position and download weather files at painfully slow speeds.

Today, however, many sailors want to be entertained and connected at sea.

Satellite communication is no longer just there to keep you safe and on the right track, but for anything from WhatsApp chats to video calls, blogging and live streaming.

To do both (or either) affordably – preservation of life and entertainment – you’re looking at installing different systems: for example, an Iridium system for emergencies and Starlink for web browsing and keeping in touch.

Maybe Starlink is your first choice for an SOS, but a satellite phone is your safety net.

Wildgoose argues that the gap between Starlink and traditional sat phones is so great that it’s easier to consider them as ‘broadband’ and ‘narrowband’ than to compare speeds.

“Think about usage,” he says. “It makes no sense to talk about how long a Netflix film will take to download over Iridium yet it takes only half a minute to download a weather forecast. So really it’s more that narrowband is limited to weather, email, perhaps a little WhatsApp, but broadband can do Netflix.”

A woman using a computer on a boat while out at sea thanks to satellite communication

Chloe Smith makes use of the Fleet One internet on board Blue Pearl. Credit: Smith Family/SY Blue Pearl

Getting your satellite receiver to talk to different devices is a complicated business, made simple by MailASail’s Red Box.

This user-friendly hub has 4G built-in and enables wifi so that users have a backup voice and email channel. It works with a combination of satellite and cellular services.

“I’ve been doing this for 20 years and there’s still no silver bullet that does it all,” says Wildgoose, who also offers after-sales support. “You need to take a bunch of everything, and we sell a product that glues it all together.”

When I visited the ARC+ rally in 2023, 86 of the 96 boats sailing from Gran Canaria to the Caribbean carried a satellite phone and 10 relied on Starlink only.

Starlink’s 50 x 30cm dish enabled the adults to live-stream the Rugby World Cup en-route to Las Palmas, while the kids caught up with their favourite cartoons on Netflix. Some sailors carried both.

Juan Borg Manduca, who was sailing around the world on B emZ, used Starlink a lot in the nine months leading up to the voyage to sort out teething difficulties on his new-build Dufour 530.

He opted for the Roam plan – covering Europe as far as the Canaries, explaining that he used the lower cost option on land, but when he left he toggled the priority to Boats and it charged €2.66 per gigabyte.

A photo of a mobile phone screen

Telegram in use during the ARC+ 23. Credit: Paul Tetlow

Nicholas Salame used Starlink on board his Oyster 575 Ahlam for work and video conferencing, and David Dias, skipper of Outremer 5X Nuvem Mágica, had both the land (Roam) and Boats Starlink packages so he could switch between the two.

“Starlink worked every time: 100% accuracy,” he said. “This year [2023] was unique because everyone was chatting throughout the whole trip. In other years people just used their satellite comms for emergencies. We were sharing pictures of fishing and food on WhatsApp.”

Claire and Malcolm Wallace used WhatsApp on their Discovery 58 to alert ARC yachts when they lost their forestay off Cape Verde. Swedish sailor Henrik Linder did the same when he lost his mast 500 miles offshore.

In the above examples, Starlink was working, but I’ve also heard unverified reports of times when it didn’t, and because its usage among sailors is relatively new, there simply isn’t a large enough sample size to give a true idea of its accuracy.

“And here is the rub,” says Ed Wildgoose. “Nobody actually knows on a given day where it’s going to work. Support and documentation on the service are based on Facebook – asking if someone is using it in location X and whether it works for them… in 2023, nobody knew whether it would work at sea. A load of people gave it a go and were happily excited when they set off across the Pacific and it did. But then it stopped working in France and came back on, and the same in Turkey. It’s also recently been terminated in South Africa.

“Starlink has to meet regulations – it’s not allowed everywhere and is being turned on and off. For an SOS, we strongly recommend either handhelds or fixed devices including Certus because they can have proper telephone handsets attached, are in known locations, you don’t have the issue of finding the right apps, and they are safety of life quality.”

World Cruising Club stance on satellite communication

To get the perspective on bluewater sailing, I spoke to Paul Tetlow, director of the World Cruising Club (WCC), which organises ARC rallies.

“We require skippers to have the ability to send and receive emails at sea,” he said. “It could be via SSB radio [via a free messaging program called Airmail] or a satcom device, which allows an instant message, whether that’s Iridium Certus 100 or Inmarsat Fleet One or something else. Rather than specifying a product we say they need to have a level of service.”

Iridium satellite communication devices

Iridium GO! with displays on paired devices. Credit: Iridium

Tetlow has been impressed with what he’s seen of Starlink.

While only two of the 20 boats leaving St Lucia at the start of World ARC 2023 had the high-speed internet service, six months later, by the time they’d completed a world circuit, only two boats didn’t have it.

“People are supplementing rather than swapping their sat comms with Starlink. Nobody has complete confidence in the coverage or the pricing model, so they’re not going to give up their Iridium system, but they will buy Starlink because of the utility they derive,” explains Tetlow.

“There’s also the risk, as some skippers have experienced, of reaching a certain number of miles offshore and being invited to upgrade from the Roam plan to the more expensive Boats plan, or otherwise lose the service altogether. The Roam package has certain protections, it’s geofenced by region and certain countries haven’t authorised it for use yet. I think there’s a speed protection on it too, where it doesn’t work at over 12 knots… things have locked down a bit in the last six months but even with the increased costs of the Boats package Starlink still meets satisfaction.”

Starlink states that coverage in local territorial waters and in motion for land is contingent on government approval.

For a map of the latest coverage (which, for example, cites availability in Europe but not in China or Russia, and only a handful of countries in Africa) see starlink.com. The main form of communication for ARC fleets nowadays is the instant messaging service WhatsApp.

“WhatsApp replicates most of what SSB does,” says Tetlow. “Each morning we have a roll call, and boats check in with their lat and long position, but over messaging, not with voice. If we have a distress situation we minimise contact, we cut out sympathy messages, because otherwise, it’s too big to control.

“Twice this year we’ve had incidents in the Pacific – equipment failure and a serious casualty – and WhatsApp came to the fore both times.”

Instant messaging service Telegram was also used by participants, mostly for announcements. Skipper David Dias said: “One thing that Telegram and WhatsApp both do very well is data compression. So for a scenario where you have low bandwidth but want to send a picture or video, they’re great.”

Which satellite communication package? Roam or Boats?

Many coastal sailors appear to use a £299 Roam (land) terminal and pay £86 per month. Starlink cites this package as ‘best for RVs, nomads and campers.’

Meanwhile, the Boats option, which Starlink says is ‘best for maritime, emergency response, and mobile businesses,’ starts at £247 per month (with a hardware cost of £2,740) and can be used in-motion and at sea.

It’s not clear how far out to sea you need to be before Roam actually stops working but Starlink states that the Mobile Priority service plan, part of the Boats package, is required for ocean use.

If you’re on Roam you need to opt in to this or change your service plan.

A red box for satellite communication in a boat

MailASail’s Red Box bonds cellular and satellite together so you’re not charged over the odds. Credit: Ed Wildgoose

Furthermore, if you exceed your data and haven’t opted in for more, it’ll stop working on the ocean, but you can still have unlimited mobile service inland (on lakes and rivers, for instance).

On Starlink’s website, the black areas on the coverage map are considered ‘Ocean’, including marinas, coastlines, and inland bodies of water.

However, it states that service is still available here for stationary use.

Ed Wildgoose points out that sailors do risk buying land terminals and have been able to make them work at sea.

However, Musk has been saying he will stop this. “We sell the maritime dish and plan. Users near the shore can almost certainly use the Roam option, but for how long will this continue?”

But what if you don’t want to pay satellite prices when you’re close enough to land that your mobile should work?

“We’re getting a lot of feedback from sailors complaining about Starlink price rises,” says Wildgoose. “They ask how they can get cellular to defray some of the costs, and MailASail’s Red Box is the solution here. This bonds cellular and satellite together.”

An allowance of 50GB may seem generous, but for anyone planning to stream video at sea, Wildgoose points out that watching Netflix costs around 0.5-2GB of data per hour.

“Those with children and a Netflix/Instagram habit may want to consider larger airtime plans as the 50G plan will offer only somewhere in the range of 25-100 hours of consumption.”

Satellite phones

For entertainment and everyday communication, there’s little argument that Starlink fits the bill.

For emergency communication, though, sat phones can also send live tracking data (a ‘breadcrumb’ trail of positions to the people back home), and GPS SOS alerts.

Note, the word ‘phone’ is used loosely here, with the caveat that it needn’t have a handset but can hook up to other devices to make voice calls.

Sat phones require a prepaid SIM card or contract, allowing users to access the handset directly or connect to smart devices (laptop, tablet or mobile) using the required software, apps and logins.

Messengers

If you don’t need voice or data, but you do need a reliable SOS service, before looking at sat phones it’s worth considering messaging services.

Rather than being charged for data, these contracts include a set number of messages.

Using the Iridium satellite network, Garmin’s InReach Mini allows two-way text messaging and can be used to trigger an SOS call to a 24/7 search and rescue centre.

A man fitting a YB3 tracker to a boat

Many cruisers who are sailing offshore and over a long period of time fit a YB3 Tracker, so family and friends can stay updated on their progress. Credit: James Mitchell

For a subscription fee, you can also receive tailored weather forecasts. With a built-in keyboard reminiscent of the old Blackberry phones, the SPOT X does a similar thing using the Globalstar satellite network and you can also connect to your phone to type text messages via an app (though it works without it).

It has a compass, programmable waypoints and an SOS button, and will send tracking data to family and friends.

The YB3 Tracker, used by ARC participants, is a fully automatic device that wakes up on a regular basis and sends a GPS position back to the YB base.

This is then recorded on a map you can access online. You can also send and receive basic messages via the device or for more advanced ones, via a Bluetooth-connected phone or tablet.

Credits are used each time you transmit: one credit per tracking position or 50 characters sent or received.

Unlike many other devices, you can rent it for an event and there are no annual contracts, suspension fees or cancellation fees.

Iridium hotspots

The budget choice, adopted by the majority of 2023 ARC+ participants was the satellite hotspot Iridium GO! which needs to be connected to a smartphone or tablet to transfer data.

Martin Whitfield, skipper of Rival 36, Topaz Rival, paired his Iridium GO! with his tablet, and used it only for GRIB files (highly compressed weather data).

 Iridium GO! satellite hotspot

Iridium GO! satellite hotspot

“It’s so slow,” he admitted, “but I don’t need it for anything else. Why on Earth would I want to have emails in the middle of the ocean?”

A downside of the Iridium GO! is that it doesn’t come with a phone handset.

You may think you don’t need one but Ed Wildgoose cites a tragic case of a skipper suffering a heart-attack at sea and his son not being able to call for help.

“He couldn’t work out how to make the mobile connect to the device. We don’t know if the world would have been different if they’d had a telephone with a green button, but in an emergency do you really want to have to break into the code on the back of something that can only be operated when paired with a mobile, and then it has to be an AIC mobile with specific software, and of course, it needs to be charged…”

New Iridium hotspots

When customers ask Wildgoose for buying advice, his first question is: ‘What do you need the sat phone for?’

Often they claim they don’t ‘need’ fast speeds, just the cheapest model, but this is coming from consumers used to home broadband. They may be in for a shock!

“To give you an example, we’re talking about a download speed that in one model would take an hour, and in another, a minute, and yet the latter costs only about 10% more,” he says.

“The incremental expense gives so much more capability that it’s hardly worth recommending the other!”

In January 2023, for example, Iridium introduced its Certus 100 service. The Skylink Redbox (made by MailASail) and GO! Exec both use this.

Though slightly more expensive, they’re 50 times faster, much cheaper for internet data and have cheaper and better quality voice.

These units can be hooked up to a real telephone (like at home) and have a wifi hotspot allowing any phone, tablet or laptop to download weather, emails or access WhatsApp.

Additionally, the Skylink Redbox has high-performance cellular 4G, a firewall to control costs and allows the user to select only the apps they want to be billed for.

When hooked up to your smartphone, Iridium Certus takes just 2 seconds to connect, compared to 30 seconds for a standard satphone, and reduces the time taken to send 10kb from one minute to a few seconds.

The download speed, at 88kbps compared to 2.4, allows social media apps, emails and basic surfing.

Thuraya SatSleeve

Another hotspot option is the SatSleeve by Thuraya, available either with its own stand or as the SatSleeve+, which comes with a clip that allows you to ‘dock’ it to your smartphone for ‘walk and talk’.

Both models come with an SOS call button that makes an outgoing call to a predefined number even if the smartphone isn’t connected.

It also has three compression settings to improve speed when browsing the internet: high (no images), low (images will be compressed), or no compression.

Iridium handsets

The ubiquitous Iridium 9555 or 9575 Extreme can be found on many boats meeting mandatory requirements for offshore events.

As Ed Wildgoose puts it, “It’s the ultimate in dependable mobile communications. It is a ruggedly built tool, not a toy. It won’t play games, take pictures, or play MP3s. What it will do is work. Everywhere.”

Iridium 9555 satellite phone

The Iridium 9555 satellite phone is easy to use

The Iridium 9575 Extreme also has an integrated speakerphone and hands-free headset.

PBO’s technical editor Fox Morgan used her Iridium 9555 to make a mayday after a dismasting in the Atlantic.

“Its simplicity and portability was a huge win for me. You don’t always need to spend the most to get what you need,” she said.

Inmarsat handsets

Inmarsat’s Sailor Fleet range of satellite phones covers a range of budgets from entry-level Fleet One (social and business emails and voice calls) to FleetBroadband (social media, VPN access and system monitoring) to Fleet Xpress (high usage browsing, business applications and on-demand bandwidth).

ARC skipper Neil Smith, has the Sailor Fleet One, which retails at around £2,670 and is run by his MailASail Red Box.

“We’ve got two sat phones – a handheld Iridium in a grab bag and the fixed Fleet One at the nav table,” he says. “Having the Red Box helped us get used to it all, and their software makes weather data a lot cheaper by compressing everything.”

A satellite communication device for receiving a satellite signal

Inmarsat Fleet One receiver. Credit: James Mitchell

The Smith family pays $140 a month for 15 minutes of voice calls and enough data for weather and communicating with the ARC fleet and HQ while at sea.

“I’m not social media orientated, and as a family, we don’t use it a lot either, certainly not while sailing,” says Neil.

Fleet One’s hardware cost is comparable to that of Starlink, but it’s worth noting that the monthly data cost is significantly less ($25/month inshore, $140/month globally).

Though this also means you get much less data at sea (a minuscule 5MB compared to 50GB), Ed Wildgoose points out that there are ‘unlimited’ tariffs of around $250 in certain regions such as the Caribbean and Med.

So if you want heavy web use inshore but SOS and tracking at sea, then Fleet One, with its safety-of-life reliability, is well worth considering.

Compression

Standard Iridium data speed is 2.4kb, and even this will vary according to signal strength.

You should always use a proper external antenna if possible. However, data can be made to ‘feel’ faster through compression.

This is essential for low-speed internet. The more you can compress an email or web page, the faster it will travel and the cheaper it will be.

Compression technology is a feature of MailASail’s Teleport IT suite. Its algorithms save up to 90% on airtime with tricks such as removing HTML and large attachments from emails and shrinking the amount of data sent by a third.

It also includes a blogging system optimised for low-speed internet connections, global marine forecasts and firewalls to stop your device from downloading background programmes.

Similarly, sat comms seller Global Telesat Communications (GTC) recommends its RedPort Optimizer and compression software, SpeedMail, to enhance data connection.

Other ways you can maximise slow-speed internet connections are by reducing image sizes, using mobile versions of websites and apps (eg Facebook) rather than desktop versions, and using web browsers that offer text-only browsing (you can choose this option on Google Chrome).

Alternatively, use the website textise.net to convert pages to text-only pages.

How call plans work

As with cellular phones, sat phones require a SIM card and data plan. These vary considerably from pre-paid options to annual contracts. Airtime providers often quote in $US and convert to local currency.

Satellite devices that use the older Iridium network charge a headline price of $1.50/min, with many plans including discounted bundles of minutes.

There are even ‘unlimited’ voice bundles starting at $30/month for unlimited Iridium to Iridium calling, whereas those using Iridium Certus have a separate data and call rate (see table) with a headline cost of around $0.39/min flat fee to most other numbers globally.

Ed Wildgoose adds: “It’s not so different to terrestrial mobile phone plans, but generally you need to engage a little more with the pricing as most of the cost is outside of the bundled monthly charges.”

Conclusion on satellite communication

While Iridium Certus and Inmarsat’s Fleet range of satellite devices are the only ones to accommodate high internet use, traditional satellite phones still have their place for safety-of-life reliability, basic voice and text communication.

But be warned, no matter how much data you buy, these are still very slow and not suited to anything larger than an email or weather GRIB file.

A man on a boat

Installing a YB3 tracker on a pushpit rail. Credit: James Mitchell

Once you require data for social media, web browsing and more, the most cost-effective solution is Starlink, but it shouldn’t be relied on in an emergency.

Airtime options are not always obvious when searching online, so before committing to a contract it’s worth discussing your needs with a satellite communication specialist who can recommend the right package for your type of cruising.

When it comes to satellite phones Ed Wildgoose uses the following analogy: “You can buy a lovely and comfortable super-fast tender. In comparison, a liferaft will score very poorly on speed and comfort. While we can’t make it a requirement to carry a liferaft, many of our customers would decide to have one, despite the fact they hope never to use it!”

A table showing all of the satellite phones which can be used by sailors

*This article was updated to correct the number of Globalstar satellites. The article stated it was 48; it is 25. We have also clarified the difference between Duplex and SPOT coverage.


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