Internet Connections for Cruising Sailors

About this page

Although data costs are decreasing as 3G, 4G and now 5G networks are expanding, limited bandwidth can still be a problem for some. This page may still help in decision making on mobile Internet connection for email purposes and more generally.

Related pages

On this page -

Internet Cafés

When available and reasonably close at hand, these are useful and economic to use. Perhaps the most important debate for many is whether to use an email service such as Hotmail or Yahoo Mail. Both are web based and can be used through any server. From time to time, both have been subject to large amounts of junk mail and, therefore, blocked by other email clients.

A disadvantage is the need to compose emails online. This may not be a particular problem in an Internet Café except that they are not the quietest places if you have a long and important message to compose. If you are going to use a computer or other device on the boat from time to time then it might be costly, or not possible, to remain connected for a long time. Working offline using an email client such as Outlook, Thunderbird or Windows Mail will be the preferred option; that will mean having to use two addresses and two sets of email.

A way round this is to use mail2web. This enables you to receive and send emails from almost any browser using your normal email account. Mail2web is straightforward to use and is a free service. Emails can be deleted without downloading them first. All three services leave read mail available on your server unless deleted.

Mobile Phones and data dongles

Cell phones as modems

A mobile phone linked to a laptop gives great flexibility. A detailed page on using the phone as a modem to link up a laptop to a mobile phone has been produced by HROA member, Ivan Andrews. An edited version is on my Phone Set up page.

Reception of mobile phone signals at sea can be uncertain because aerials are likely to be optimised for use on land. Over 10 miles out, and less in places, reception may not be possible. One trick is to use Bluetooth to connect the phone to the computer and then put the phone in a safe container and lift it up the mast - a maximum of 10 m from the computer. That can improve reception. It is also important to identify a mobile phone service that is reliable. This can vary from time to time and, when roaming, it pays to try the various operators by using “Manual operator selection.”

"Dumb” cell phone

Instead of using the cell phone as a modem, an alternative is to use the phone itself to send and receive emails, With connection, hard wire or Bluetooth, the information received can be passed to the computer when necessary eg a GRIB file attachment. The advantage here is that the risk of downloading virus affected email is minimised and that of downloading Windows and other updates is avoided.

Data dongles

One problem with using a cell phone as a modem is that roaming data costs can be large. Ideally, you need to buy a local SIM card but these may not always work in your phone. The shops may not be able to help you getting all the set-up details correct - especially if their English or your knowledge of the local language is poor.

It can be easier to set up and use a data dongle. There can be problems in paying for SIM cards, dongles and the monthly data volume. In Spain we found that the Orange was quite happy to sell us the dongle but that we could only buy a monthly allocation using cash in the shop. In France, Orange would not sell us a dongle because we did not have a French bank account. They would not take credit, debit card or cash. SFR (Vodafone) were more helpful although we still have to buy extra data volumes in a shop and not on-line.

The situation is changing in that it is now possible to buy a PAYG SIM card in the UK and use it abroad, albeit for a limited period. A 12 month SIM card with 12 gb of data costs about £30 from the 3 cell phone company. You can use it abroad for 2 months from time of first use in another cpuntry. If abroad for longer than that, then simply buy two SIM cards but use them both in the UK before departing.


The rapid development of Smartphones and tablets is changing the scene rapidly. Speeds with 3G and 4G are much greater than with GPRS (2,5G). The development of a wide range of apps is making it possible to receive and display not only texts of forecasts but GRIB files as well. See my page on GRIB apps


In harbour, you might be able to use a WiFi connection. Prices can vary greatly but, in France, Spain and Portugal WiFi was often free or low cost. Signal strength can vary greatly in marinas. There are aerials that can improve reception but these can be expensive. We have found in marinas that our laptop with its built in aerial often worked well.

Sometimes it is possible to piggy back on a private unsecured wireless connection. This is becoming rarer and is illegal in the UK.

Satellite Phones

No doubt, these will become cheaper to buy and use in time. If you really want to use a telephone connection at sea wherever you are, then these may be the solution. For many, costs will mean that email may be the primary use. I have no direct experience and cannot comment further at this stage.

However, the sponsor of this site, specialises in internet connection via Mobile phone for cruising around Europe and Iridium/Inmarsat satellite phone connection for crossing oceans. In addition, MailASail can advise on, supply, fit and commission all onboard communication systems. They also supply all Inmarsat FleetBroadband and Iridium Satellite Phones, along with Contract and PrePaid Airtime, and their award winning Email Compression System, ExpressMail


Inmarsat-C can give connections for email or other text purposes but is too slow otherwise. It could be used with the various services involving GRIB code and ftp services discussed on the email page. Again, I have no direct experience and cannot comment further. Cost and speed rules them out for coastal sailors but, for blue water sailors Inmarsat-C is a component part of the GMDSS. As such it is worth serious consideration.

Amateur and Marine HF Links

See also the page on HF and HAM radio.

Three choices for HF/SSB radio providing email services. There are commercial operators which, obviously, work for a profit. There is SailMail, which offers user funded co-ordination of ground stations. There is also HAM radio and Winlink.

Commercial companies are likely to have their proprietary software packages. HAM radio or SailMail users can receive and send emails, using Airmail, a messaging program similar to Microsoft Outlook. Using Airmail, they can use the Saildocs service that provides GRIB files, text retrieval and other services.

For advice on setting up these services see the RCC notes page on this site For examples of what can be received see my GMDSS texts pages.

Until such time as satellite telephone services becomes less costly, this seems to be a viable solution to accessing Internet products when at sea and out of mobile telephone contact. For those willing to make the effort, or are just interested in becoming qualified amateurs, HF radio offers a cost-effective alternative to Internet access and email. However, due to propagation and reception problems it may not be available 100% of the time.


If you have been using email in an Internet Cafe, it can be possible for the next customer to access your email address and to use it as the reply address for junk mail and worse. If you think that this might be likely, then reboot before you leave.

Remember that others might be able to "see" into your computer when on-line using hard wire, WiFi, GPRS or 3G connection. If doing any form of commercial transaction, it is wise to "Clear history" immediately. Any sensitive material including notes about passwords should be kept in an encrypted document (a facility available using WinZip or RAR). After use, remember to delete the un-encrypted version and, to be quite sure, empty the recycle bin.

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