# St. Martin travel eSIM guide > Saint-Martin mobile guide: two dialling codes on one island, 220 and 110 volt sockets, how to call across the border, Wi-Fi in bars, SFR's roaming list and emergency numbers for both sides. Page: https://esimnest.com/saint-martin/guide/ Saint-Martin is the French half of an island that has no border, so a phone user crosses between two telephone systems without noticing: the French side uses the code +590 and the Dutch side +1 721, and the electricity differs too. The official tourist office's FAQ sets out how to dial across the island and lists emergency numbers for both sides, including sea rescue on channel 16. SFR Caraïbe's roaming page includes Saint-Martin in its list of covered places, and the UK Foreign Office covers entry and safety for both Saint-Martin and Saint-Barthélemy. This guide combines those sources, and says where we found no operator page with prices. By eSimNest Team. Facts last checked 2026-10-02 against the sources listed at the end. ## Two dialling codes on one island The Saint-Martin tourist office says the international code for the French side is +590 and for the Dutch side Sint Maarten is +1 721. From a French-side number, a call to another French-side number uses the 10-digit number, while calling the Dutch side means dialling 00 1 721 54 and five digits for a landline, or 00 1 721 55 and five digits for a mobile. From the Dutch side, a call to the French side uses 00 59 followed by the 10-digit number, and a call within the Dutch side uses the 7-digit number. Calls to France use 00 33 and the 10-digit number, and calls to the United States use 001 and the area code. Check how your operator charges calls across the island. Save your hotel's number in the international format, and check your operator's terms for both sides. ## Internet providers, Wi-Fi in bars and power sockets The tourist office says the internet service providers on the island are Orange Caraïbes, Dauphin Telecom and Canal Box, that fibre optic cables are being installed, that broadband is available in most districts, and that internet access is available in bars and restaurants, where you usually need only ask for the Wi-Fi password. It adds that hotels generally have Wi-Fi in rooms or communal areas, and that free internet is one of the services hotels offer. For devices, it says the French side uses 220 volts and 60 hertz with European sockets and the Dutch side 110 volts and 60 hertz with American sockets, and that shops on both sides sell converters and adapters. A phone charger that handles both voltages is fine, but check before plugging in other equipment. ## SFR Caraïbe's list of places covered by roam-like-at-home SFR Caraïbe's roaming page lists the European places where its customers are billed at their home rates, and the list includes Saint-Martin and Saint-Barthélemy among the French overseas territories, as well as the Canary Islands, the Azores and Madeira. It says the provisions do not apply to 4G mobile-internet plans whose data is blocked outside the Antilles, and that it may check for abuse, so the list applies to SFR plans rather than to every visitor's SIM. A visitor with a plan from another operator should ask that operator whether Saint-Martin is treated as France, as the EU, or as a separate zone. We found no prepaid or visitor product on the pages we read, so the practical options are a home plan with roaming, a foreign travel eSIM or a local prepaid card bought in a shop. ## Three months without a visa, ID within four hours, and the open border The UK Foreign Office says UK visitors can stay in Saint-Martin and Saint-Barthélemy without a visa for up to three months, that a passport must have an expiry date at least three months after departure, and that there is no physical border between the French and Dutch territories on Saint-Martin, so people and goods may travel freely between the two sides. It says you must be able to prove your identity when asked, or within four hours at a police station, with a passport, a photocard driving licence or other government documentation. It adds that French laws apply, that crime levels are low but you should avoid isolated areas, including beaches, after dark, and that you can drive with a UK licence. Rules differ by nationality, so check the French consulate for your own passport. ## Sea rescue: 196, channel 16 and the island's lifeboat station The tourist office lists sea rescue contacts: the SNSM station on Saint-Martin with an emergency mobile number and a station telephone, and CROSS Antilles-Guyane on 196 or a Martinique number, or on VHF channels 16 and 73. It also lists the Louis Constant Fleming hospital in Marigot, French Red Cross and ambulance companies, and the police and gendarmerie posts. If you take a boat trip, save 196 and the SNSM number in your phone. We found no official statement on offshore coverage. ## Emergency numbers on both sides of the island For the French side, the UK Foreign Office gives 112 for ambulance, fire and police, or 15, 18 and 17 respectively, and the tourist office lists 15 for urgent medical help, 17 for police and 18 for fire. For the Dutch side, the tourist office lists 911 for police, 912 for an ambulance, 919 for fire and 910 for the hospital, each with a local landline number. Save both sets, since you may cross the island several times a day. Our Saint Martin plan page covers data before you arrive. Emergency calls: Many travel eSIMs carry data only, and a data-only profile may not place a normal phone call. Keep a voice-capable SIM for emergencies, such as your home SIM or a local plan, and save the local emergency number from this guide. Plans and current prices for St. Martin: [eSIM for St. Martin](https://esimnest.com/saint-martin/). ## Questions ### What are the dialling codes? +590 for the French side and +1 721 for the Dutch side, according to the tourist office. ### How do I call the Dutch side from the French side? Dial 00 1 721 54 plus five digits for a landline or 00 1 721 55 plus five digits for a mobile, says the tourist office. ### Is there free Wi-Fi? The tourist office says that in most bars and restaurants you just need to ask for the Wi-Fi password to use the internet free of charge, and that hotels generally have Wi-Fi in rooms or communal areas. ### Are the sockets the same on both sides? No. The French side uses 220 volts with European sockets and the Dutch side 110 volts with American sockets. ### Is there a border? No physical border, according to the UK Foreign Office. ### Do I need a visa? The UK Foreign Office says UK visitors can stay up to three months without one. Rules differ by nationality. ### What are the emergency numbers? On the French side 112, 15, 17 and 18, and on the Dutch side 911, 912 and 919, according to the sources above. ## Sources - [St Martin tourist office: useful information](https://www.st-martin.org/us/organizing-your-stay/useful-informations/) - [SFR Caraïbe: European roaming](https://www.sfrcaraibe.fr/forfaits-mobile/voyager-avec-sfr/roaming-europeen/) - [GOV.UK: St Martin and St Barthélemy entry requirements](https://www.gov.uk/foreign-travel-advice/st-martin-and-st-barthelemy/entry-requirements) - [GOV.UK: St Martin and St Barthélemy safety and security](https://www.gov.uk/foreign-travel-advice/st-martin-and-st-barthelemy/safety-and-security) - [GOV.UK: St Martin and St Barthélemy getting help](https://www.gov.uk/foreign-travel-advice/st-martin-and-st-barthelemy/getting-help)